The South Korea-U.S. Combined Forces Command will lead Ulchi Freedom Guardian, an annual joint military exercise slated for August, in a move to enhance joint defense capabilities against North Korea, officials said Thursday.

To prepare for the transfer in April 2012 of wartime operational control from Washington to Seoul, the South Korean military has been in charge of the exercise with the American forces assuming a supportive role since 2008.

The change comes amid heightened tensions on the Korean Peninsula following the March 26 sinking of the South’s corvette Cheonan, which the Seoul government holds Pyongyang responsible for. The incident took the lives of 46 sailors.

“(The military) believes that it is important we prepare against North Korea’s possible infiltrations, regional provocations and its asymmetric forces. As a follow-up measure in the wake of the Cheonan case, the UFG will be led by the CFC,” Joint Chiefs of Staff spokesman Col. Park Sung-woo said in a press briefing.

The commander of the U.S. Forces Korea had led both the South Korean and American forces up to 2007 during the command post exercise based on computer simulated war games, which demonstrates the two militaries’ joint war scenario, Operation Plan 5027.

In 2008 and last year, the South’s JCS has led the two-week exercise.

A local news report said that the change appears to be in connection with the ongoing discussions on the delay in the handover of wartime operational control. However, the Ministry of National Defense denied it.

South Korea voluntarily handed over its peacetime and wartime operational control to the U.S.-led U.N. command on July 14, 1950, after the Korean War broke out on June 25. The South regained peacetime control in 1994 and is scheduled to take back wartime control on April 17, 2012.

Conservatives here have called for a delay of the transfer, arguing that the South’s military is not fully ready to independently lead wartime operations amid continuing military threats and provocations from the communist state.

There are currently around 28,500 U.S. troops stationed here mainly for war deterrent purposes against the North.

By Song Sang-ho  (sshluck@heraldcorp.com)