Kim Jong Il (file photo)

North Korean leader Kim Jong Il has replied to a personal letter from President Bush that urged the reclusive leader to fully disclose his country's secretive nuclear activities.

The White House says the reply was sent through diplomatic channels in New York. North Korea and the United States do not have formal relations.

Under a six-nation agreement, North Korea promised to begin dismantling its nuclear facilities and to declare all of its nuclear programs by the end of this month. In return, Pyongyang was promised energy assistance and political concessions.

President Bush's letter urged Pyongyang to keep its promise. In response, North Korea said it will live up to its obligations, and it hopes the U.S. will keep its end of the deal.

At the White House Friday, President Bush noted that he had gotten Kim Jong Il's attention. He said the way forward for North Korea is to declare all of its nuclear materials and programs.

U.S. nuclear envoy Christopher Hill delivered the Bush letter while in North Korea last week.

Some information for this report was provided by AP and Reuters.