NATO Secretary-General Mark Rutte has issued a stark warning to the UK and its allies: significantly increase defence spending or face serious security threats.

Speaking in London at Chatham House following a meeting with Prime Minister Sir Keir Starmer, Rutte stressed the need for NATO members to commit 5% of their GDP to defence. He made it clear that failure to do so could compromise national security, saying:

"If you do not do this... you could still have the NHS or your pension system, etc., but you had better learn to speak Russian."

Rutte did not specify a deadline for the 5% target but confirmed discussions with allies were ongoing. He emphasized that the proposed spending includes 3.5% for core military needs and the remaining 1.5% for broader defence and security-related investments, such as infrastructure and industrial capacity.

"5% is not just a random number. It's based on hard facts. We need a quantum leap in our defence capabilities," he said, calling for a 400% increase in air and missile defence.

During their meeting at No. 10 Downing Street, Sir Keir reaffirmed the UK’s commitment to NATO:

"We see NATO as the cornerstone of our defence – the most effective military alliance in history."

The Prime Minister also highlighted the importance of ensuring NATO remains robust for decades to come, while Rutte praised the UK’s strategic defence review, particularly its focus on innovation and industrial readiness.

"It is really making a big impression in Brussels," Rutte noted.

The remarks come ahead of a crucial NATO summit in The Hague, where leaders are expected to formally adopt the 5% GDP defence spending goal – a move Rutte described as a “defining moment” for the alliance. Photo by World Economic Forum from Cologny, Switzerland, Wikimedia commons.