South Korea began an annual two-week joint exercise with more than 30,000 US troops amid North Korean contestation. According to Yonhap news agency, 56,000 South Korean troops, including 3,000 from overseas, were taking part in the Ulchi Freedom Guardian drills.

The drill will test defences against North Korea. Asia One reports that the drill is ‘largely’ computer-simulated and does not involve field training. General James Thurman, commander of the US troops based in South Korea described the joint exercise as “a key exercise in strengthening the readiness of Republic of Korea (South Korean) and US forces”.

Pyongyang criticized the military exercise as a ‘precursor to war’ and vowed to strengthen its nuclear deterrent.

South Korean president Lee Myung-bak recently urged Pyongyang to consider “transformation” and reforms.