UK in most dangerous period I've known, UK Chief of the Defence Staff tells BBC

His remarks come ahead of the expected publication of the Defence Investment Plan in the next few weeks, following repeated delays.

The document, which will set out how new equipment and defence infrastructure will be funded over the coming decade, was first due to be released in autumn 2025.

On Friday, the prime minister said the plan would be published before a Nato summit "in just a few weeks' time".

Sir Keir Starmer said: "We've been working on that defence investment plan for some time, very closely with our armed forces, as you would expect, because we need that interaction."

Asked about recent criticism of the UK's diminished capabilities by the former defence secretary, Lord Robertson, and whether the government is willing to give the military the extra funding it has said it needs, Sir Richard said he was confident ministers are aware of the threats and are increasing spending.

"Exactly as the prime minister says, we need to spend more on defence and do it faster. The challenge for ministers is to make those difficult trade-off decisions," he said.

He told Today: "Closer to home we have seen in 2026 more long-range aviation from Russia. These are strategic aircraft that will go well into our own airspace. We've seen as many in 2026 as in 2025."

The airspace he referred to is the High North - which includes the Arctic circle and areas adjacent to it.

The RAF intercepts Russian jets approaching UK airspace. However, there is no recent case of Russian military aircraft actually entering UK airspace, which is 12 nautical miles from the UK.

Sir Richard also spoke about the changing nature of warfare and the need to adapt.

Drones and autonomous systems are going to become "increasingly important in the future of warfare", he said.

On the threats posed to the UK, he said: "I'm very clear that this is the most dangerous time I have known in my working life.

"And the risks and threats to this country are greater than I have known since the Cold War.

"And it is important that society and all of us recognise and understand that and that may mean that we need to make different choices and different priorities."

Russia is probing both the UK's "traditional military defences" and also through other means, such as cyber, sabotage and assassination attempts, he said.

"So Russia is definitely raising the stakes and risks crossing a line," he said.

In a hard-hitting speech in April, Lord Robertson warned that the UK's security is "in peril" and Sir Keir's government has shown "corrosive complacency" towards defence.

In a directly political intervention, Lord Robertson - who is now a key government adviser - warned in his speech: "We cannot defend Britain with an ever-expanding welfare budget."

He said: "We are under-prepared. We are under-insured. We are under attack. We are not safe... Britain's national security and safety is in peril."

He added: "There is a corrosive complacency today in Britain's political leadership."

At the time, Downing Street said: "We've set out our spending targets on defence, the UK defence budget is already rising to record levels and we're going further."