The U.S. Defense Department has ruled out military action against North Korea despite President Barack Obama's hint at possible changes to Washington's policy toward Pyongyang.

The Associated Press Saturday quoted U.S. Pentagon press secretary Geoff Morrell as saying military action is not the focus of Washington's efforts.

He said the U.S. is not moving toward military action against the North, adding the preference is to prevail over the North Koreans with diplomatic or economic pressure.

President Obama had earlier promised a stronger response against Pyongyang, saying his government will not continue a policy of rewarding provocation.