Pentagon chief says U.S. will not 'overreact' to North Korea missile launches

U.S. Defense Secretary Mark Esper arrives for the first day in his new post at the Pentagon

TOKYO (Reuters) - U.S. Defense Secretary Mark Esper said on Tuesday that the United States will not overreact to a series of missiles launches by North Korea in recent weeks and would keep the door open to talks with Pyongyang.

North Korea fired missiles into the sea off its east coast for the fourth time in less than two weeks, the South Korean military said on Tuesday, as Pyongyang protested that joint U.S.-South Korea military drills violated diplomatic agreements.

"The key is to keep the door open for diplomacy ... we're not going to overreact to these, but we monitor them, we watch them closely and we're cognizant of what's happening," Esper told reporters traveling with him to Japan.

(Reporting by Idrees Ali; editing by Darren Schuettler)