UK military chief warns of most dangerous period since Cold War, urges faster defence spending

Chief of the Defence Staff Sir Richard Knighton said on Friday that the UK faces its most dangerous period since the Cold War, with Russia probing defences and raising the stakes, and urged faster defence spending ahead of a long-delayed investment plan.

"This is the most dangerous period that I have known," Knighton told BBC Radio 4's Today programme. He said Russia has been "probing, challenging, testing our defences" and that "Russia is definitely raising the stakes and risks crossing a line."

Knighton said in 2026 there have been as many long-range Russian aviation incursions into UK-associated airspace as in all of 2025. The airspace he referred to is the High North, including the Arctic circle. Russia is also probing through cyber, sabotage and assassination attempts, he said.

"We need to spend more on defence and do it faster," Knighton said. "The challenge for ministers is to make those difficult trade-off decisions."

The Defence Investment Plan, which will set out how new equipment and defence infrastructure will be funded over the coming decade, was first due in autumn 2025 and has faced repeated delays. Prime Minister Keir Starmer said the plan would be published before a NATO summit "in just a few weeks' time." The NATO summit is scheduled for July 7.

Media reports cite a £28 billion ($38 billion) shortfall in defence funding over four years. Starmer has pledged to lift defence spending to 3% of national output in the next parliament.

Former defence secretary Lord Robertson warned in April that UK security is "in peril" and accused the government of "corrosive complacency" towards defence. Robertson, who served as Britain's defence secretary in the 1990s and later as NATO secretary general, said in a speech: "We cannot defend Britain with an ever-expanding welfare budget."