South Korea and the United States will begin the Key Resolve joint military exercise Monday amid heightening tensions following the North's recent missile test and the killing of its leader's half brother, the defense ministry said.

The computer-simulated command post exercise will be held until March 24.

During the period the ministry plans to heighten the level of alertness against the North's possible provocations.

The allies are also conducting Foal Eagle, a field training exercise involving ground, air and naval forces. It started March 1 and will run through the end of April.

North Korea denounced the joint drills as a rehearsal for invasion.

The ministry said the nuclear-powered USS Carl Vinson aircraft carrier will arrive in the southern port of Busan on Wednesday to take part in the exercises. (Yonhap)