WASHINGTON (AP) _ President Bush pleaded with North Korean leader Kim Jong Il in a letter to keep his promise to fully disclose all nuclear programs by year's end, in the most personal Bush diplomatic approach toward Pyongyang since he called the country part of the ``axis of evil.''
Bush sent the letter to the North Korean leader on Dec. 1. The same day, he also sent similar letters to the other nations involved in the six-party nuclear talks reiterating his desire to resolve the nuclear standoff with the communist regime.
The White House would not disclose copies of the correspondence.
``He sent a letter to Kim Jong Il that urged the North Koreans to fully declare their nuclear programs, as called for in the September 2005 six-party agreement,'' Gordon Johndroe, a spokesman for the National Security Council, said Thursday.
White House press secretary Dana Perino said the president decided to send the letter to ``so that we can keep it all on track.'' U.S. nuclear envoy Christopher Hill delivered the letter to North Korean Foreign Minister Pak Ui Chun during his recent trip to Pyongyang, according to the Korean Central News Agency said.
On Thursday, Hill suggested that negotiations had stalled on producing a draft declaration of North Korea's nuclear programs by the end of the year. That required is part of an agreement reached in February among the six parties, which include the United States, North Korea, Russia, China, Japan and South Korea.
Under the deal, North Korea was promised 1 million tons of fuel oil or the equivalent, plus political concessions such as its removal from a U.S. list of terrorism-supporting nations, in return for disabling its nuclear program and making other moves.
``The disablement activities are going well,'' Perino said. ``I would characterize it as timely because we are nearing the deadline by which they had to declare.''
But the letter represented a turnaround for the president, who once called North Korea part of an ``axis of evil'' along with Iran and prewar Iraq, and halted direct U.S. talks with the Communist country after he came into office.
Bush earlier this week exhorted Iran to ``come clean'' on its nuclear intentions in the wake of a U.S. intelligence report which said Tehran actually had abandoned that goal a few years ago.
The letters to the leaders of Russia, China, South Korea and Japan reiterated the U.S. commitment to the six-party negotiations with Pyongyang and Bush's desire to successfully get North Korea to make a full declaration, Johndroe said.
Secretary of State Condoleezza Rice expressed optimism.
``It is going to take a monumental effort to get all of this done by the end of the year,'' she said, speaking to reporters on Thursday as she flew to Brussels for NATO meetings. ``And I am not too concerned about whether it's December 31st or not. They seem to be on track. Everybody believes the cooperation is very good.''
North Korea began disabling its reactor, which was shut down in July, and two other facilities last month under the watch of U.S. experts. It has promised to complete the process by the end of December, but South Korean nuclear envoy Chun Yung-woo said last week it would take longer to remove about 8,000 spent fuel rods from the reactor.
Hill said investigators were seeking to clear up questions over North Korea's purchase in past years of gas centrifuges for its nuclear program.
On the declaration, Hill told reporters in Beijing, where he was meeting diplomats following his visit to North Korea, that Washington and Pyongyang still had differences to resolve on the issue.
In comments early Thursday, South Korean Foreign Minister Song Min-soon sounded a gloomy note, saying: ``There has not been progress on the declaration yet.'' A Japanese Foreign Ministry spokesman expressed disappointment that North Korea was likely to miss the year-end deadline, but that it is unlikely to affect the overall agreement.
Hill said some sort of substantive declaration was needed, even while implying that it might not constitute a final document. He said the draft could be submitted first through China, North Korea's ally, which has hosted four years of denuclearization talks.
Potential complications include North Korea's alleged uranium enrichment program and the true amount of separated plutonium that it declares. The U.S. accused North Korea in late 2002 of seeking to secretly enrich uranium in violation of an earlier disarmament deal, sparking the latest nuclear standoff.
Speaking in Seoul, Song called on the U.S. and North Korea to allow some wiggle room on the issue.
``The issue of nuclear declaration is not easy,'' he told reporters. Each side ``should take a flexible attitude.''
The centerpiece of the North's program is the Yongbyon nuclear complex, which includes a reactor, reprocessing plant and fuel fabrication plant. Hill visited the facility on his recent trip and declared that he was satisfied that disablement work there was proceeding on schedule.
The United States alleges that North Korea began a uranium enrichment program with help from a nuclear black market run by A.Q. Khan, the founder of Pakistan's atomic weapons program.
Those technologies are believed to include centrifuges used to enrich nuclear materials, and Hill said the U.S. was discussing the matter with Pyongyang in order to trace the program's origins and ensure it had been terminated.
``A lot of people try to suggest that what's past is past, but actually, I think being clear on what happened is also a means for us to build a future relationship,'' Hill said.
Chinese Foreign Ministry spokesman Qin Gang said the six countries were consulting on whether to hold another round of meetings before the end of the year.