An annual joint military exercise between South Korea and the US has begun despite claims from North Korea that the drill is a sign of military cooperation against it.

The military drill, codenamed Key Resolve, is aimed at practising the defence of South Korea in case of emergencies, while another exercise, Foal Eagle, will focus on counter-infiltration exercises to improve combined and joint operational cooperation between the two militaries.

Around 10,000 US troops and 8,000 reinforcement personnel will participate in the joint drill for the Key Resolve exercise and 20,000 South Korean troops will be involved in the Foal Eagle, according to

The joint military exercise is scheduled to end on 18 March 2010.