The United States says it remains committed to six-country talks to end North Korea's nuclear program, despite Pyongyang's hostile rhetoric towards its southern neighbor and U.S. ally.

North Korea announced Friday that it is canceling all political and military agreements with South Korea - the latest action in a series of threats against South Korea's pro-U.S. president, Lee Myung-bak.

U.S. State Department spokesman Robert Wood said Friday that Pyongyang's comments are not helpful. But he said the United States has not detected any movement of North Korean troops or equipment accompanying Friday's statements.

Wood also said the United States will continue to pursue an end to North Korea's nuclear weapons program through the six-party talks. He said Secretary of State Hillary Clinton plans to meet with regional leaders to discuss the situation with North Korea.

South Korea also downplayed Pyongyang's statement. Officials in Seoul expressed "deep regret" about North Korea's stance and urged Pyongyang to engage in dialogue to resolve their differences.

North Korea's Committee for the Peaceful Reunification of Korea issued a statement, published by the official Korean Central News Agency, declaring that North Korea would no longer honor accords struck with the south, including a Yellow Sea border agreement.

The Yellow Sea border between the two nations was demarcated by a U.S.-led United Nations command at the end of the Korean War.

The two countries fought deadly skirmishes along their border in 1999 and 2002.

The North also accused the Seoul government of pushing the two countries to the brink of war.

North and South Korea technically remain at war, since they never signed a peace treaty to end the 1950 to 1953 Korean conflict.

Some information for this report was provided by AFP.