NATO Secretary General Mark Rutte on Monday was due to urge a "400-percent increase" in the transatlantic alliance's air and missile defense capacities in response to the threat from Russia.
"We see in Ukraine how Russia delivers terror from above, so we will strengthen the shield that protects our skies," Rutte was due to say in a speech to the Chatham House think-tank in London, according to comments quoted in a statement.
To maintain credible deterrence and defense, he was to say that NATO needs "a 400-percent increase in air and missile defense".
His comments come ahead of a NATO summit in the Netherlands this month where US President Donald Trump is pressuring alliance members to announce a major boost in their military budgets.
Trump is pushing NATO members to increase their defense spending to five percent of their gross domestic product (GDP), up from the current target of two percent.
US Secretary of Defense Pete Hegseth said last week in Brussels that the allies were close to an agreement on the five-percent target, which could be formalized at the summit in The Hague.
NATO members have been scrambling to bolster their defense capabilities since Russia launched its war against Ukraine in February 2022.
"Danger will not disappear even when the war in Ukraine ends," Rutte was to say, according to AFP.
"We need a quantum leap in our collective defense... We must have more forces and capabilities to implement our defense plans in full."
"Our militaries also need thousands more armored vehicles and tanks, millions more artillery shells."
Rutte will visit London next week, where he is expected to welcome Britain's new defense strategy.
Britain announced plans last week to build up to 12 nuclear-powered attack submarines and six munitions factories to rearm the country in response to Russia's invasion of Ukraine.
