South Korea and the United States launched an annual joint military exercise Tuesday despite warnings from Pyongyang that the drill will damage hopes for peace on the peninsula.

Tens of thousands of American and South Korean troops are taking part in the joint naval drills in the Yellow Sea off the west coast of the peninsula.

The bilateral Combined Forces Command said the 10-day, computer-assisted exercise is aimed at improving its ability to prevent current and future external threats to South Korea and the region.

U.S. General James D. Thurman, the CFC commander, says the forces are applying lessons learned in Iraq and Afghanistan, “as well as those garnered by the Alliance's recent experiences with North Korean provocations.”

A small group of South Korean peace activists gathered in front of the South Korea-U.S. Joint Command in Seongnam Tuesday morning to protest the drill.

Pyongyang called the exercises provocative and said they were targeted against North Korea.

A report in the official North Korean news agency Tuesday accused the allied forces of exercising for an invasion of North Korea simultaneously by air, water and land.

The United States has close to 30,000 troops regularly stationed in South Korea as a deterrent against the North's attacks.

The communist government in Pyongyang routinely denounces military drills in the South as practice for an invasion. Washington and Seoul reject the claims.

Senior North and South Korean officials met last month in Indonesia for their first talks since North Korea shelled a border island, killing four South Koreans in November. Relations already were strained over the sinking of a South Korean warship in March 2010.

The United States has held talks with officials of both Koreas in recent weeks on steps needed to resume six-nation talks on North Korea's nuclear disarmament.