Clinton and Gates to hold talks in South Korea on July 21

U.S. Secretary of State Hillary Clinton speaks during a joint news conference with Georgia's President Mikheil Saakashvili in Tbilisi July 5, 2010. REUTERS/David Mdzinarishvili

WASHINGTON (Reuters) - The secretaries of state and defense, Hillary Clinton and Robert Gates, will travel to South Korea for bilateral talks with their counterparts on July 21, the Pentagon said on Monday.

The talks are expected to focus on strengthening security ties amid heightened tensions between the two Koreas after the sinking of a South Korean warship in March, widely blamed on North Korea.

Pyongyang has denied responsibility and a U.N. Security Council resolution last week condemning the attack stopped short of directly blaming the reclusive North.

The United States has about 28,000 forces in South Korea, which remains technically at war with the North nearly six decades after the end of the 1950-53 Korean War.

The U.S. military had long planned to hand over wartime operational control of Korean forces by 2012. But President Barack Obama and South Korean President Lee Myung-bak agreed last month to push back that date until the second half of 2015.

The delay was meant to send a clear message about U.S. staying power in the region and had been under discussion months before warship’s sinking, U.S. officials say.

Reporting by Phil Stewart; Editing by Sandra Maler