President Barack Obama said on Tuesday he expects more posturing and provocation by North Korea and, while he does not believe the Asian nation has the capacity to mount a nuclear weapon on a ballistic missile, the United States is preparing for "every contingency."

"I think all of us would anticipate that - you know, North Korea will probably make more provocative moves - over the next several weeks," Obama told NBC's "Today" show.

"But our hope is that we can contain it and that we can move into a different phase in which they try to work through diplomatically some of these issues," he said.

The interview was conducted on Monday before the bombings that killed three people and injured more than 100 people in Boston.

After a series of belligerent steps and statements in recent weeks, Pyongyang has issued new threats against South Korea demanding an apology for anti-North Korean protests.

The North has also rejected U.S. overtures for talks, but a U.S. military official said the North Korean leadership was looking for a way to cool down its charged rhetoric.

Obama said he believes North Korea's saber rattling is similar to past patterns of behavior. Even so, the United States is taking precautionary measures, he said.

"We have to make sure that we are dealing with every contingency out there," the president said. "And that's why I've repositioned missile defense systems - to guard against any miscalculation on their part."