The drills could trigger a response from North Korea, which has used previous exercises as a pretext for weapons tests.

The drills could trigger a response from North Korea, which has used previous exercises as a pretext for weapons tests.

The drills could trigger a response from North Korea, which has long portrayed the exercises as invasion rehearsals.

The United States and South Korea kicked off their annual summertime joint military exercise on Monday, amid efforts by Seoul to improve relations with North Korea.