Japan and the United States ended two days of high-level talks in Washington on Friday, agreeing to keep a close eye on North Korea's reaction following last week's six-party talks on Pyongyang's nuclear arms programs, a Japanese official said.

During the talks, Vice Foreign Minister Yukio Takeuchi and U.S. Deputy Secretary of State Richard Armitage traded views on the message North Korea will issue on the 55th anniversary of its foundation on Tuesday, the official told reporters.

Japan and the U.S. are expected to closely watch whether North Korea will take provocative measures, such as declaring itself a nuclear power, testing nuclear weapons or test-launching missiles.

At the six-party talks, Pyongyang threatened to declare that it possesses nuclear arms and test them unless the U.S. abandons what Pyongyang calls a hostile policy toward it. Japan, China, South Korea and Russia were the other participants in the Beijing meeting.