The deal with Anduril was agreed ahead of UK Defence Secretary John Healey's meeting with US counterpart Pete Hegseth in Washington on Thursday.

The contract is backed by the International Fund for Ukraine, a UK-administered funding mechanism that uses financial contributions from international partners to procure military equipment for Kyiv.

It will see Ukraine receive cutting-edge Altius 600m and Altius 700m drones, which are designed to monitor an area before striking targets that enter it, "over the coming months," the UK government said in a press release.

"We are determined to achieve a secure, lasting peace in Ukraine, which means putting Ukraine in the strongest possible position to prevent any return to Russian aggression," said Healey.

"With a pound2.26 billion loan from seized Russian assets, plus pound1.6 billion worth of air defence missiles announced for Ukraine in the last week, the UK is continuing to show leadership in securing a lasting peace for Ukraine," he added.

Intense and sometimes fractious talks are underway between the US, Ukraine and its European allies to try and achieve an end to the conflict, which erupted in 2022 when Russia invaded eastern Ukraine.

President Donald Trump has paused US military aid to Ukraine, leaving Europe shouldering the burden of keeping Kyiv's armed forces equipped.

Trump's suspension of aid has hardened fears in Kyiv and across Europe that Ukraine could be forced to accept a peace on terms favourable to Moscow.