Sir Keir Starmer will present Donald Trump with a plan to send fewer than 30,000 European troops to Ukraine in an attempt to secure American protection for the deployment.

The Prime Minister is expected to detail how European forces could police any ceasefire deal brokered by the US president when the pair meet in Washington next week.

But he will urge Mr Trump to have US fighter jets and missiles on standby in Eastern Europe to respond with lethal force if Russia breaks the terms of any armistice, according to Western officials briefed on the plans.

The Anglo-French strategy for a “reassurance force” was presented to Europe’s most powerful leaders at an emergency meeting in Paris earlier this week as they scrambled to respond to Mr Trump opening peace talks with Vladimir Putin.