Britain will supply 100,000 drones to Ukraine by April 2026, the Government has said.
The significant delivery pledge represents a ten-fold increase on the number of drones given to Ukraine last year.
John Healey, the Defence Secretary, will announce a 50-nation Ukraine Defence Contact Group meeting in Brussels today.
The £350 million drone package is part of a broader £4.5 billion military support initiative for Ukraine.
In addition to drones, Britain said it had already shipped 140,000 artillery shells to Ukraine since January and will spend a further £247 million this year training Ukrainian troops.
As part of the Strategic Defence Review published on Monday, the Government announced that more than £4 billion would be spent on autonomous systems and drones for the UK Armed Forces.