Secretary General Mark Rutte said NATO needs a “quantum leap” in defence to deter threats to the alliance, as he called for Western allies to invest more in their Armed Forces.

In a speech at London's Chatham House think tank, he said Russia could be ready to use military force against NATO within five years.

Rutte said NATO needed a “400% increase in air and missile” to credibly defend itself against attacks, BBC reported.

He said he expected NATO allies to agree to spend 3.5% of economic output on military spending and another 1.5% on “defense-related expenditure” such as roads, bridges, airfields and seaports. He said he is confident the alliance will agree to the target at its summit in The Hague on June 24-25.

The new target would meet a demand by U.S. President Donald Trump that member states spend 5% of gross domestic product on defence. Trump has long questioned the value of NATO and complained that the U.S. provides security to European countries that don’t contribute enough.

With little let up in fighting in Russia's war against Ukraine despite ceasefire calls, European countries are under pressure to raise defence spending after Trump signaled a shift in policy, pushing for the region to better protect itself.

Several countries say they are doing so, with Britain pledging an increase from 2.3% to 2.5% of GDP by 2027 and 3% of GDP at a later date. Germany has said it will need roughly 50,000 to 60,000 additional active soldiers under new NATO targets.

Like other NATO members, the U.K. has been reassessing its defense spending since Russia’s invasion of Ukraine in February 2022. UK’s Prime Minister Keir Starmer has pledged to increase British defense spending to 2.5% of gross domestic product by 2027 and to 3% by 2034.

At present, 22 of the 32 member countries meet or exceed NATO’s current 2% target. (BBC; Reuters; Agencies; Photo © Reuters)