Russia’s air defences could shoot down Britain’s nuclear missiles

 Moscow could soon have strong enough air defences to intercept Britain’s Trident nuclear missiles.

A new report warned that improvements to the Russian capital’s surface-to-air systems could render the nuclear deterrent ineffective in the event of a major war.

Sidharth Kaushal, a missile expert who authored the Royal United Services Institute report, said the ability to strike Moscow “underpins the credibility of Europe’s independent nuclear deterrents”.

The think tank suggests that the UK and France could no longer be sure of the effect of launching their nuclear deterrents in the event of a conflict in the next decade.

The report also said that Britain and Europe will have to build hypersonic missiles to defeat Russia’s improving air defences and maintain the effectiveness of the nuclear deterrent.

“It is not certain that they [Russia] will intercept every submarine-launched ballistic missile but potentially also not a certainty that the required number will get through,” Mr Kaushal said.

The findings are based on a missile intercept rate of roughly 90 per cent, as achieved by Israel and the US in 2024 during two long-range barrages of around 200 ballistic missiles each.

If Russia can replicate that level of success, then the British and French strike capabilities might not be able to deliver the desired effect.

The report highlights two Russian systems, the ground-based A-235 anti-ballistic missile system, designed to deflect nuclear strikes, and the S-500, which is believed to be capable of intercepting intercontinental-range ballistic missiles.

The S-500 Prometheus can reportedly hit targets more than 300 miles away.

Nuclear warheads require a precise, synchronised implosion to initiate the chain reaction leading to a major explosion.

Missile interceptors slamming into nuclear warheads would be unlikely to trigger such a detonation, but would cause debris to fall from the sky.

“In the coming decade, an increasingly robust ballistic missile-defence system around Moscow may emerge, in the form of the A-235 and the S-500, which may form a layered defence,” Mr Kaushal wrote.

Britain and France can only deliver strategic nuclear strikes via their fleets of submarines.

They also possess a significantly smaller number of warheads than the United States, which allies are no longer sure would come to Europe’s aid in the event of a war with Russia.

The UK currently maintains a stockpile of approximately 225 nuclear warheads. Around 120 are considered operational, with approximately 40 deployed at sea at any given time aboard one of the four Vanguard-class Royal Navy submarines.

Russia has the world’s largest arsenal of nuclear weapons, with 5,459 nuclear warheads, 4,300 of which are operational.

Rachel Reeves has come under pressure to spend more on defence sooner. Military chiefs have warned about the renewed threat from Moscow, while the Armed Forces are suffering from a string of issues, including staff shortages.

Sharon Graham, the boss of Labour’s biggest union donor, has urged Sir Keir Starmer “to do what he said he would do” after the Prime Minister promised last year to boost defence spending to 2.5 per cent of GDP by 2027.

Ms Graham, the general secretary of Unite, has told Sir Keir that he must sack the Chancellor if she continues to block a rise in defence spending.

Ms Graham accused Ms Reeves of compromising the UK’s national security and putting “thousands” of British jobs at risk by delaying a rise in military investment.

Ms Reeves is blocking a rise in defence spending this year despite mounting pressure from military chiefs to invest in a rapid rearming of the country.

She has been urged to boost the Ministry of Defence (MoD)’s day-to-day spending budget amid fears of a £28bn hole in the department’s finances.

But the Chancellor ruled out an immediate increase in defence funds last week, saying the MoD would have to wait for “future spending reviews” before pouring billions more into Britain’s military.

The professional head of the Armed Forces and head of the RAF have both spoken out about defence funding in recent weeks, arguing that ministers should press ahead with their long-delayed defence investment plan, which is expected this spring.

European defence spending has been highlighted by Donald Trump since his return to the White House a year ago, with renewed demands for more military spending from allies.

European leaders have talked about the need for the Continent to step up and ensure its own security, given fears that the US could scale back assistance to Europe.

Compared to Europe’s nuclear superpowers, the United States has enough warheads in its arsenal to overwhelm Russia’s air defenses, no matter how developed they are in the coming years.

Dr Kaushal said: “The US absolutely could do it, overwhelmingly, irrespective of how well or otherwise the Russian missile defences develop.

The Russian plan, according to the analyst, would be to survive the initial American strikes to launch their own retaliation. 

“There’s no theoretically or practically viable Russian system that could keep Moscow or any other part of Russia safe from the US arsenal, if they decided to throw their weight at it indefinitely,” Dr Kaushal added. 

Earlier this month, Sir Keir told Nato countries at a security summit in Munich that he wanted to accelerate the rearmament of Europe, arguing: “To meet the wider threat, it’s clear that we are going to have to spend more, faster.”

Britain lags behind China and Russia in developing hypersonic missiles.

The weapons fly at speeds exceeding 5,000 mph, making them difficult to intercept. Russia has reportedly already used them to bomb Ukraine. 

Earlier this month, the UK announced it will develop new long-range precision and hypersonic weapons to destroy enemy warships, in partnership with France and Italy.

Called Stratus, the missile will have two variants: a hypersonic one and a stealth variant, which will not travel faster than the speed of sound. They will be fitted to the Navy’s new Type 26 frigates.

However, development of these missiles will likely take years, with Britain not expected to see such weapons available until the 2030s. 

Last year, Sir Keir Starmer announced Britain would buy at least 12 new F-35A stealth jets capable of carrying nuclear warheads.

The jets are among the most sophisticated in the world, with defence sources saying they have the ability to slip past most modern air defence networks undetected.

Unlike Trident missiles launched from a British submarine, the warheads dropped from the F-35s would likely be American-built B61 “gravity bombs”.

They would effectively be dropped from the stealth jets and glide to their targets, meaning the jets would need to fly deep within Russian territory to target Moscow.

The use of the American-made weapons would likely require prior approval from Washington, as well as from a security council within Nato, since they are not sovereign to the UK.  

It is unclear when any new defence spending increase could be announced. Ms Reeves delivers her Spring Statement on March 3.

A MoD spokesman said: “Our nuclear deterrent protects us every minute of every day and is the ultimate guarantee of our national security. We keep our nuclear posture under constant review so that we can adapt to the actions of our potential adversaries, including assessment of the defensive measures that they might use.

“This month we announced over £400 million investment in long-range precision weapons, including hypersonic missiles, showing how we’re investing in critical new technology.”