SEOUL, South Korea -- South Korea and the United States have begun annual military drills that North Korea calls a precursor to war.

The U.S. says the two-week Ulchi Freedom Guardian drills started Monday with more than 80,000 troops from the U.S., South Korea and seven countries that fought with them in the 1950-53 Korean War.

Pyongyang has repeatedly threatened to attack Seoul over perceived insults and denounces the exercises as preparation for a pre-emptive attack.

Seoul is still angry over a North Korean rocket launch in April that the United Nations called a front for a banned long-range missile test. North Korea says it was a satellite launch.

Pyongyang's official media says leader Kim Jong Un recently visited a military unit involved in a deadly 2010 artillery exchange with South Korea.

In Washington, State Department spokeswoman Victoria Nuland said the exercises are routine and urged North Korea to refrain from "bellicose statements."