Camerons arrive in Washington for Obama visit
13 March 2012 Last updated at 19:33 GMT
David Cameron, accompanied by his wife, Samantha, has arrived in Washington for a three-day visit, with Afghanistan expected to dominate his talks with US President Barack Obama.
The two men are expected to agree to hand control of combat operations to Afghan forces by the middle of next year, months earlier than planned.
The BBC's Ben Brown reports.