The U.S. and South Korean military chiefs warned on Tuesday that North Korea could "conduct provocative actions" in response to large-scale joint drills between the two countries, as China's premier also said tensions could lead to conflict.

"The chairmen recognized the possibility that North Korea could conduct provocative actions during the Key Resolve/Foal Eagle exercise, or in connection with North Korean major political events in April," a statement from Chairman of the U.S. Joint Chiefs of Staff General Joseph Dunford's office said, referring to the U.S.-South Korean military exercises.

The statement said the two military leaders "discussed response options" during a call that lasted about 30 minutes.