Sir Keir Starmer is to announce a new package of support for Ukraine, despite Donald Trump piling pressure on Kyiv to back down and accept a peace deal with Russia.

The Telegraph can reveal that the Prime Minister will use the third anniversary of Russia’s invasion to unveil a “triple whammy” of measures, including military aid and sanctions, on Monday.

It is in stark contrast to the approach taken by Mr Trump, who has in recent days called Volodymyr Zelensky, the Ukrainian president, a “dictator” and is pressing for a speedy end to the conflict.

Amid a widening split between the US and Europe over the Ukraine war, the US president on Friday accused Sir Keir of doing “nothing” to bring the conflict to a close.

The US also indicated that it could leave an international effort to prosecute Russia for war crimes.

The differences between London and Washington will be put under a spotlight when Sir Keir visits the White House for face-to-face talks with Mr Trump on Thursday.

In an attempt to calm any tensions, The Telegraph understands that during the trip Sir Keir is expected to finally announce the date – most likely to be 2030 – by which 2.5 per cent of UK GDP will be spent on defence.