The threat to ships carrying oil in the Middle East is at its worst since the Iran war started, experts have said, after a spate of attacks on another key route in the region.

The warning comes after a number of attacks on vessels in the Red Sea, an alternative waterway that some tankers had been using since Iran blocked the Strait of Hormuz.

Iran has denied Donald Trump’s claim that it was in talks with the US over reopening the strait, but said it was speaking to Oman about securing the shipping lane.

“In terms of threat to the trade of crude, we’re at the worst period that we’ve been in since this since this crisis began,” said Matthew Wright, an analyst at ship-tracking firm Kpler.

The number of ships passing through the Strait of Hormuz was just eight on Sunday and 11 on Saturday, compared with more than 100 per day before the war began, according to Kpler.

Before the conflict, about 20% of the world’s oil and gas passed through the strait.

The temporary peace deal with the US struck in early June led to numbers rising again, but the resumption of strikes between the two countries roughly a month later have significantly reduced traffic.

Many ships have been “going dark” when crossing the strait, meaning they turn off their transponder to avoid detection.

For much of the war, some ships carrying oil from Saudi Arabia had instead passed through an alternative shipping lane in the Red Sea, between the kingdom and northeast Africa.

But a recent spate of attacks by Yemen’s Houthi fighters on Saudi tankers using the alternative waterway has further heightened the risks.

Yemen’s Houthis say they have attacked two Saudi oil tankers in the Red Sea as the US launched its 12th consecutive night of strikes on Iran.

Iranian state media said two people had been killed in the US strikes on Wednesday, and a tanker caught fire in an explosion in a mined route in the Strait of Hormuz.

Ahead of the latest round of strikes, US President Donald Trump had threatened to destroy an Iranian bridge or power plant if Iran attacked a ship in the strait and to “take care of” the Houthis if they blocked the Red Sea.

If confirmed, the Houthi attack would be the first since the Iran-backed group announced a “maritime embargo” against Saudi Arabia.

The Houthis named the tankers as the Encelia and the Layla, though their responsibility has not been confirmed.

The group’s military spokesperson Yahya Saree said they had targeted the ships with drones and missiles for allegedly violating its naval blockade.

Saree added that the Houthis promised to continue their naval operations and would continue “enforcing the ‘siege for a siege’ equation”.

The state-run Saudi Press Agency confirmed early on Thursday that the Encelia was struck “while sailing in the Red Sea”, resulting in a fire on its bow.

Citing an unnamed official source at the Transport General Authority, it described the attack as a violation of international law. All crew were safe, it reported.

UK Maritime Trade Operation (UKMTO) reported an “unknown projectile” struck a Saudi tanker about 130km from Al Shuqaiq in Saudi Arabia at 20:00 GMT. The attack caused a fire but no casualties, it said.

British maritime risk management group Vanguard also reported that the Saudi tanker Encelia had been hit.

The attack on the Layla has not been confirmed.

US Central Command (Centcom) said at 21:30 GMT it had launched strikes at Trump’s direction “to further degrade Iran’s ability to threaten civilian mariners and commercial vessels transiting regional waters”.

The strikes targeted “Iranian military targets including maritime capabilities, missile and drone storage facilities, coastal surveillance sites, and air defense assets,” it said.

Kuwait, Jordan and Bahrain soon reported responding to airborne threats, before Iran’s military said they had targeted US assets in all three countries, according to AFP.

Iranian state media reported two people had been killed in US strikes on the country’s south near its border with Iraq.

Meanwhile, the Iranian Revolutionary Guard (IRGC) said the Strait of Hormuz was “completely closed” after an explosion in the channel, Iranian state media reported.

The IRGC said it had stopped three oil tankers from passing through the strait.

One tanker caught fire and two others turned back after attempting to pass through a mined route south of the strait, according to Iranian state media.

It comes after Trump promised earlier on Wednesday to attack an Iranian bridge or power plant if its forces hit ships in the Strait of Hormuz.

Iran’s Foreign Minister Abbas Araghchi later warned of an “eye for an eye” response to attacks on Iran.

On Tuesday, Trump told reporters he would “take care of the Houthis” should they obstruct the Red Sea as they had said.

Few details of the “maritime embargo” were given by the Houthis when it was announced on Monday, but a media official said they were closing the Bab al-Mandab Strait – the Red Sea’s southern gateway – to Saudi vessels.

Renewed fighting has broken out in the Gulf region, in the worst exchange of fire between the US and Iran since the two nations signed an interim deal in June.

US Central Command (Centcom) said on Tuesday it had launched “powerful” strikes in response to attacks on three oil tankers in the Strait of Hormuz, hitting more than 80 targets including air defence systems, coastal radar and fast boats.

On Wednesday, Iran said it had targeted US military sites in Bahrain and Kuwait in retaliation to the US attacks.

Oil prices ticked up following the strikes, with a barrel of Brent crude rising by more than 3% to $76 (£56.88).

Nato chief Mark Rutte described the American strikes on Iran as “absolutely necessary”, speaking at the military alliance’s summit in Ankara, Turkey.

“I think it was absolutely necessary,” Rutte said, arguing that Iran was “basically violating the ceasefire” given what “happened yesterday with ships being attacked”.

“I think it is totally crucial that the US forcefully [reacts].”

The US also said it had revoked its temporary suspension of sanctions on Iranian oil sales. Iran’s speaker Mohammad Bagher Ghalibaf accused the US of breaching their Memorandum of Understanding (MoU) on this issue, and others, including the attacks in southern Iran and “violating Iranian adjustments in the Strait”.

“The era of bullying and extortion is over. It leads nowhere. We don’t fold,” he said.

The US strikes hit Qeshm island, Bandar Abbas and Sirik, Iranian state media reported, where people have been injured by shrapnel.

Missiles and drones were launched at “85 key US military facilities” in the two countries, including a US Navy headquarters and an air base in Kuwait, the Islamic Revolutionary Guard Corps (IRGC) said.

Iranian media reported the first casualty of the strikes, with IRNA stating: “Guardsman Mohammadreza Khazini was killed while confronting enemy drones after being struck by shrapnel from a projectile.”

Kuwait has also responded to the Iranian strikes on its country, lambasting the “repeated attacks”.

Talks on reaching a permanent deal have been on pause with funeral proceedings taking place for the late Ayatollah Ali Khamenei, killed on the first day of US-Israeli strikes on Iran.

Ceremonies are taking place in Iraq on Wednesday, with the final rites and burial set for Mashhad in north-east Iran on Thursday.

It is not clear when talks will resume after this latest round of strikes.

Now, weeks after Iran allowed the partial reopening of the strait – under a ceasefire agreement with the US that is mostly holding – the sea is calm once more and fishermen are returning.

One of them, Abdol Rahman, took the BBC through the strait for a close-up view of how the war has affected life in and around Bandar Abbas.

As we sailed through the strait, two container ships seized by the IRGC in April, at the height of the conflict, came into view.

At the time, the IRGC said the vessels had endangered maritime security “by operating without the necessary permits and tampering with navigation systems”.

Despite the ceasefire, the MSC Francesca and the Epaminondas, which were flagged to Panama and Liberia respectively, have not been released.

Dozens of other cargo ships could be seen offshore, waiting for permission from the Iranian authorities to pass through the strait.

As we approached Hormuz Island, 8km (five miles) off the coast of Bandar Abbas, our guide Rahman pointed out an old fortress overlooking the sea.

Its weathered red walls are a reminder that control of the strait has been fought over for centuries. Built in the early 16th Century, it was central to the Portuguese Empire’s control of this vital waterway – until 1622 when Portugal was driven out by Shah Abbas I of Persia, after whom Bandar Abbas is named.

The U.S. Air Force is intensifying efforts to protect its most vulnerable yet indispensable aircraft — aerial refueling tankers and heavy airlifters — by exploring a new class of “kinetic” self-defense systems designed to physically destroy incoming missiles rather than merely confuse or jam them.

Senior officials say the concept, still under development, would act as a final protective layer for high-value airborne assets such as the KC-46 Pegasus, KC-135 Stratotanker, C-17 Globemaster III, C-5M Super Galaxy, and C-130 Hercules. These aircraft form the backbone of American global power projection, enabling fighter jets and bombers to operate across vast distances while delivering cargo and troops into contested regions.

But as adversaries field longer-range and more sophisticated anti-air weapons, the survivability of these large, non-stealthy platforms is increasingly in question.

Kevin Stamey, the Air Force’s Program Executive Officer for Mobility and Director of the Air Force Life Cycle Management Center’s Mobility Directorate, recently outlined the service’s interest in kinetic self-protection during an official interview.

“Some technology that we are really looking at is kinetic self-protection for our high-value airborne assets,” Stamey said. “Because the threat is evolving, we are trying to develop a capability to protect the tanker that is independent of that threat.”

He described the concept as a “last line of protection” — a capability that would engage a missile physically if electronic countermeasures fail.

“If all else fails and a threat somehow breaks the kill chain, we’ll still have a means to protect the tanker,” he explained. “Whether it’s an IR seeker or a radar seeker, if we have a means of taking it out kinetically, we don’t have to electronically attack it or use decoys that are effective against some things, but not others.”

The remarks reflect growing concern inside the Air Force that traditional defensive tools — such as electronic warfare (EW) jamming, flares, and towed decoys — may not be sufficient against emerging missile technologies.

For decades, tankers and airlifters have relied on layered defensive systems that disrupt or mislead incoming missiles. These include radar warning receivers, chaff and flare dispensers, and directional infrared countermeasures (DIRCM) that use lasers to blind heat-seeking missiles.

Laser-based DIRCM systems are already deployed across portions of the tanker and airlift fleet. However, these systems are designed to confuse infrared-guided threats rather than destroy them. They are ineffective against radar-guided missiles and do not physically eliminate the incoming weapon.

The problem is compounded by the rapid evolution of missile seeker technologies.

Imaging infrared seekers, for example, are resistant to radiofrequency jamming and radar cross-section reduction techniques. They are passive sensors, meaning they do not emit signals that can be detected by the target aircraft. Radar-guided missiles, meanwhile, increasingly employ advanced signal modulation techniques that complicate jamming efforts.

Air forces worldwide are racing to develop cognitive electronic warfare systems capable of adapting in real time to new threat waveforms. The “holy grail,” as defense officials often describe it, would be a self-learning system that autonomously counters unfamiliar threats mid-mission.

Yet even the most advanced EW suite may eventually be outpaced. That possibility is driving renewed interest in kinetic solutions.

The Air Force has experimented with miniature missile-based self-defense concepts for more than a decade.

In 2015, the Air Force Research Laboratory (AFRL) publicly revealed a project known as the Miniature Self-Defense Munition (MSDM). The concept envisioned an “extremely agile, highly-responsive” interceptor roughly one meter long — about a third the size of an AIM-9X Sidewinder.

The missile would use a low-cost passive seeker and be small enough to carry in multiple numbers aboard large aircraft.

AFRL initially awarded contracts to Raytheon and Lockheed Martin for development work. In 2020, Raytheon received additional funding to produce a flight-test-ready miniature self-defense missile, suggesting the effort remained active.

While few details have emerged publicly, analysts believe such a system would operate similarly to hard-kill active protection systems used on armored vehicles — detecting an incoming projectile and launching a small interceptor to destroy it before impact.

In 2017, Northrop Grumman patented a kinetic aircraft protection concept centered on miniature interceptors, reinforcing the idea that industry sees potential in this approach.

The U.S. Navy also explored similar territory in 2018 with a call for information on a Hard Kill Self Protection Countermeasure System for transport and tanker aircraft.

Missile interceptors are not the only kinetic concept under consideration.

In recent years, the Air Force has tested the ability of KC-135 tankers to deploy small drones from standardized Common Launch Tubes. These drones could serve multiple functions, including acting as decoys, extending sensor coverage, or even engaging incoming threats.

Unlike a one-shot miniature missile, a drone could loiter and potentially engage multiple targets. It could reposition after launch and even re-engage if necessary, reducing the risk of wasting interceptors in a complex attack scenario.

However, magazine depth — the number of defensive shots available — remains a major challenge. Aircraft have limited space and weight capacity. Reloading in flight is difficult, though larger platforms like tankers offer more flexibility than fighters.

Future solutions may blend interceptors, drones, and directed energy systems into a layered defensive ecosystem.

Directed energy weapons, particularly high-energy lasers, are often discussed as a solution to the magazine depth problem because they theoretically offer deep or near-unlimited shots constrained only by power supply.

However, while ground-based laser systems have matured significantly, airborne laser weapons capable of reliably destroying incoming missiles have proven far more challenging. Power generation, cooling requirements, and beam control at altitude remain technical hurdles.

For now, operational airborne lasers in U.S. service are limited to DIRCM systems that blind infrared seekers rather than destroy the missile outright.

The push for kinetic self-defense is closely linked to the Air Force’s evolving operational concepts.

Future conflicts, especially in the Indo-Pacific, are expected to feature adversaries with long-range anti-air capabilities extending hundreds or even thousands of miles. China’s People’s Liberation Army has invested heavily in extended-range air-to-air and surface-to-air missiles designed specifically to target enabling assets such as tankers and airborne early warning aircraft.

“Our adversaries are building long-range threats specifically to push assets like our tankers further back,” Stamey noted. “They believe it’s easier to target and shoot a tanker than an F-35 or F-47.”

That calculation is central to modern anti-access/area denial (A2/AD) strategies. By forcing tankers to operate farther from the fight, adversaries reduce the effective range and persistence of U.S. fighters, including stealth aircraft such as the F-35 Lightning II and the emerging F-47 sixth-generation platform.

If tankers can survive closer to contested airspace — inside what planners call the “weapons engagement zone” — they can dramatically enhance operational flexibility.

The Air Force’s exploration of kinetic self-protection also feeds into the broader debate about the Next Generation Air Refueling System (NGAS).

Air Mobility Command chief Gen. John Lamontagne has described NGAS as a wide-ranging examination of future tanker concepts, from traditional large aircraft to business-jet-based platforms, blended-wing designs, and even signature-managed or stealthy tankers.

Central to those discussions is how much survivability should be built into the platform itself versus added through defensive systems.

A stealth tanker could reduce detection risk, but stealth comes at significant cost and design trade-offs. Alternatively, a conventional tanker equipped with advanced connectivity, sensors, electronic warfare, and kinetic self-defense might achieve acceptable survivability at lower cost.

The optimal mix remains under study.

A kinetic interceptor is only as effective as the sensors that cue it.

Detecting a high-speed incoming missile — potentially traveling at Mach 4 or faster — requires advanced infrared search and track systems, radar coverage, and rapid data processing.

The Air Force is investing heavily in distributed sensing and networking, enabling aircraft to share threat data in real time. Loyal wingman drones or escort aircraft could contribute to a shared defensive picture, providing earlier warning and better engagement geometry.

Such networking would be crucial in a saturation attack scenario, where multiple missiles approach from different angles.

The renewed emphasis on kinetic self-protection reflects a broader shift in airpower thinking. For decades, the United States operated largely uncontested in the air domain. Tankers and airlifters rarely faced sophisticated long-range threats.

Peer competitors are fielding advanced missile systems, over-the-horizon sensors, and integrated air defense networks capable of reaching far beyond traditional front lines.

In that environment, high-value support aircraft can no longer rely solely on distance for protection.

By adding a kinetic “hard kill” layer to their defenses, tankers may gain a fighting chance against even the most advanced threats — preserving the mobility backbone that underpins U.S. global operations.

While significant technical and integration challenges remain, Stamey’s remarks make clear that the Air Force sees kinetic self-protection not as a futuristic luxury, but as an emerging necessity.

As adversaries continue to extend the reach and lethality of their anti-air arsenals, the contest between missile and countermeasure is entering a new phase — one in which the tanker itself may soon be armed to shoot back.

The United Kingdom is preparing to expand its capacity to act against so-called “shadow fleet” oil tankers suspected of circumventing sanctions on Russian, Iranian, and Venezuelan oil exports. British ministers have identified a domestic legal framework that could allow the military to board, detain, or divert certain vessels operating without valid national flags, after financial and monitoring measures have proven insufficient to curb maritime sanctions evasion.

Officials stressed that no UK military boarding operations have yet taken place, but preparatory work has been underway for several weeks to determine how Royal Navy forces could be used to enforce shipping sanctions against unflagged or falsely flagged vessels. The move reflects growing concern that existing sanctions and monitoring mechanisms have not halted continued illicit maritime activity, particularly the movement of oil linked to sanctioned states.

The legal basis for potential action is rooted in the Sanctions and Anti-Money Laundering Act 2018. Provisions within the legislation allow authorities to detain, control, or restrict the movement of ships identified as disqualified or operating under false or illegitimate registration. The Act also enables enforcement measures against vessels owned, operated, or controlled by designated individuals or entities connected with sanctioned states. UK ministers believe these clauses can be interpreted to authorize military involvement, including the use of force if necessary, against unflagged or falsely flagged tankers. According to officials, such vessels fall outside the legal protections typically afforded at sea and can therefore be treated as disqualified ships under UK law.

A UK government spokesperson described the interpretation as an escalation in enforcement tools rather than a shift in sanctions policy. Future operations could see Royal Navy surface vessels stopping and detaining ships, supported by surveillance aircraft and, if authorized, special forces boarding teams. Potential actions could include controlled boarding, diversion to port, or enforced removal from UK waters. However, ministers emphasized that political authorization and detailed operational planning would be required before any military measures are taken.

The UK’s reassessment comes amid a more assertive approach by the United States, which has moved from enforcement of financial and regulatory sanctions toward direct interdiction at sea. Over recent weeks, US authorities have seized five oil tankers linked to sanctioned oil flows from Russia, Iran, and Venezuela. Notable examples include the Marinera (formerly Bella 1), intercepted in the North Atlantic with UK surveillance and maritime support, as well as the Olina and the Skipper, vessels accused of attempting to move sanctioned Venezuelan or Russian oil under false or rapidly changing flags. In many cases, these ships were evading sanctions by reflagging to states such as Guyana, Timor-Leste, or Russia, or by operating without valid insurance and opaque ownership arrangements.

The US seizures represent a significant shift in sanctions enforcement, moving beyond port restrictions and financial penalties to physically removing vessels from service when other measures have failed. UK officials have confirmed that countering the Russian shadow fleet is a government priority, and that lessons from US operations are informing UK planning.

Shadow fleets, as described by Western authorities, are networks of oil tankers designed to sustain exports from sanctioned states. These fleets have expanded significantly since 2022, often comprising older vessels purchased on secondary markets after Western owners exited Russian, Iranian, or Venezuelan trades. Shadow fleet tankers commonly change names and flags, sometimes multiple times a year, and often register under jurisdictions with limited oversight, including Guyana, Panama, Liberia, Timor-Leste, or Russia itself. This practice allows sanctioned states to maintain oil exports despite price caps, insurance restrictions, and port denials.

Several high-profile vessels illustrate this pattern. The Marinera, formerly Bella 1, and the Olina repeatedly altered their names and flags while continuing sanctioned trade routes. Estimates from allied governments suggest that the global shadow fleet comprises more than 1,000 vessels, a number that has steadily grown as sanctions tightened. Many of these ships operate without coverage from major insurers, relying instead on non-recognized or opaque insurance arrangements—or operating without any coverage at all. This exposes coastal states to significant financial and environmental risks in the event of accidents, such as collisions, groundings, or oil spills. Past incidents in the Baltic Sea, North Sea, and Mediterranean have reinforced concerns about safety standards and maritime hazards posed by these fleets.

The UK government reports that it has imposed sanctions on over 500 vessels linked to shadow fleet networks. Coordinated action with international allies has reportedly forced approximately 200 of these ships out of active service, either through seizure, denial of port access, loss of insurance, or other logistical disruptions. Alongside sanctions, UK authorities have intensified checks in surrounding waters, stopping more than 600 ships near the British Isles to verify compliance and insurance coverage. Officials noted that a significant proportion of inspected vessels lacked valid insurance or clear flag registration, highlighting risks to UK coastal waters and shipping lanes.

Beyond maritime enforcement, the UK has expanded sanctions targeting the Russian oil sector itself. British authorities have joined the US in sanctioning major Russian energy companies, including Gazprom Neft and Surgutneftegas, alongside traders, insurers, and shipping entities involved in oil exports. Hundreds of tankers have also been designated under these measures, restricting their access to finance, insurance, and ports. The combined goal is to disrupt revenue streams from Russian oil sales and weaken the logistical networks sustaining sanctioned exports.

Officials emphasize that financial sanctions alone have proven insufficient to halt shadow fleet operations, prompting the UK to pursue a multi-layered approach combining financial measures, maritime enforcement, and potential military action. While military seizure remains a contingency, the strategic intent is clear: to close gaps in enforcement that have allowed sanctioned oil to continue moving globally despite international restrictions.

Observers note that the UK’s potential move toward military involvement in sanction enforcement reflects broader shifts in international approaches to sanction evasion. With shadow fleets increasing in size, sophistication, and reach, authorities in the UK, US, and EU face mounting challenges in monitoring and intercepting vessels operating outside conventional regulatory systems. The UK’s readiness to explore military options underscores a willingness to integrate naval power, surveillance capabilities, and legal authority to confront a persistent maritime challenge.

Experts caution, however, that military operations against unflagged or falsely flagged vessels are legally and operationally complex. Issues of jurisdiction, rules of engagement, and potential diplomatic fallout must be carefully managed. Moreover, the dispersed nature of shadow fleets, often operating in distant international waters, complicates both detection and interdiction. Despite these challenges, UK officials argue that the risk of inaction—allowing sanctioned oil to continue flowing—outweighs potential operational difficulties, particularly when coordinated with allied enforcement efforts.

In the coming months, UK authorities are expected to continue refining legal interpretations, operational planning, and coordination with allies to enable rapid action if required. While ministers have not specified timelines for potential military operations, the preparatory work signals a significant escalation in the UK’s ability to counter sanctions evasion at sea. Officials emphasize that any action would follow careful political and operational authorization and aim to enforce compliance with international sanctions while minimizing risks to personnel and commercial shipping.

The combination of financial, regulatory, and potential military measures illustrates the evolving approach to maritime sanctions enforcement. As shadow fleets grow in both size and sophistication, the UK, alongside international partners, appears prepared to adopt a more assertive posture to ensure that sanctions regimes have meaningful impact, safeguarding both the integrity of international sanctions and the security of critical maritime routes.