British fighter jets to be armed with nuclear bombs, as UK faces 'new era of threat' of war with Russia

1 June 2025, 10:12 | Updated: 1 June 2025, 12:12

Britain is looking to purchase fighter jets capable of launching lower-powered gravity bombs in an effort to counter threats of nuclear escalation from Russia.

The Labour government is engaged in sensitive talks over the development, which would be the biggest expansion of the UK's nuclear deterrent since the Cold War.

The American-made jets would be capable of launching tactical gravity bombs with lower power than conventional nuclear weapons.

Possession of lower-powered tactical nuclear weapons would allow the UK and its allies to deliver a clear and limited response to a Russian attack without risking escalation into a full-blown nuclear war.

The move is backed by John Healey, the defence secretary, and Admiral Sir Tony Radakin, the head of the armed forces. Sir Keir Starmer has also given his support, and discussions are believed to have taken place with the US Department of Defense.

The prime minister will launch the government's ten-year defence plan on Monday, which will recommend the UK considers expanding its contribution to Nato's shared nuclear deterrence in Europe. The review will not commit specifically to air-launched capabilities.

Read More: Spending review ‘natural point’ to put UK on path to further boost defence

Read More: Government announces £1.5bn in extra funding for military homes

British military chiefs believe the UK must hold more nuclear capabilities as a deterrent to Russia.

Russian President Vladimir Putin has repeatedly threatened nuclear escalation in recent years.

There are growing concerns that Russia could employ the use of nuclear weapons in its war with Ukraine or on the eastern front of Nato.

An attack on a Nato member country would begin a conflict between the military alliance and Russia, as an attack on one member is considered as an attack on all. It is unclear, however, if a limited tactical nuclear strike by Russia would result in a full nuclear retaliation.

Defence Secretary John Healey has acknowledged that the UK must adapt to the "new era of threat" it faces.

Healey told The Sunday Times: "The world is definitely becoming more dangerous. Nuclear risks are rising."

"We face now, for the first time since the end of the Cold War, seriously increasing risks of state-on-state conflict.”

Admiral Radakin is said to view the expansion of the nuclear deterrent as the UK's biggest defence priority and has long been privately in favour of air-launched capabilities.

The nuclear-armed fighter jets would act as a second pillar of the nuclear deterrent, and could be employed in a scenario below full nuclear war.

Britain is currently the sole major nuclear power with only one platform - submarines - from which to launch nuclear weapons.

The United States has a nuclear triad, meaning it is capable of launching weapons from land, air, and sea.

British submarines are capable of launching lower-powered bombs, but there are concerns that enemies would not be able to distinguish between tactical bombs and high-powered nuclear warheads capable of destroying cities.

There are fears that such a miscalculation could spark a full-scale nuclear war.

Senior sources have indicated that the UK is primarily looking to purchase Lockheed Martin's F-35A Lightning stealth fighter jet. The jets have a range of 1,4000km and can carry the B61 thermonuclear gravity bomb.

The bomb has a yield of between 0.3 and 0.4 kilotons. Comparatively, the bomb dropped by the United States on the Japanese city of Hiroshima during World War Two had an estimated yield of 15 kilotons (15,000 tons of TNT).

Monday's strategic defence review seeks to place Britain on a pre-war footing. It will include proposals for rearmament and the revival of an "always-on" defence industry prepared for the threat of war with Russia.

The government will invest £6 billion on munitions to replenish UK stockpiles, commit to new defensive shields to protect Britain against enemy ballistic missiles, and recommend the re-establishment of a civilian home guard.

The review will also back a resurgence in Navy shipbuilding, launch a new underwater surveillance programme to guard against Russian sabotage of internet cables and energy pipelines, and set a long term target for increasing the size of the army.

Simon Case, the former cabinet secretary and nuclear deterrent expert, urged the government last week to develop a second method of launching nuclear deterrent.

He said: "Deterrence depends on your adversary being certain that you can do real harm to them in the ultimate case. In my view you wouldn’t rely on a single system for anything."

“As I look out on my children’s lives, the next ten and probably 20 years is going to be dominated by this inter-state conflict. It feels to me that we across the western alliance need to get our skates on and be ready.”

Case is one of the few people in Britain who knows the exact number and location of Britain's nuclear warheads. The UK is believed to own 225, around half the peak stockpile of 520 the UK had in the 1970s.

The previous Conservative government have supported the move to establish air-launched nuclear capabilities.

James Cartlidge, the shadow defence secretary, said: “I recently called for our deterrent to be strengthened by diversifying how we deliver nuclear weapons, so I welcome the commitment to reintroduce air-launch capabilities … but there are two big caveats."

"First, it underlines why 2.5 per cent GDP on defence is unlikely to be enough and we believe the government should commit to spending 3 per cent this parliament, if we are to adequately boost both conventional and nuclear forces."

“Secondly, the priority on nuclear must still be to make our strategic continuous at sea deterrent (CASD) even more resilient."