By MATTHEW LEE – 3 hours ago TOKYO (AP) ― Senior U.S. and Chinese diplomats worked Wednesday to lure North Korea back into an international effort to rid the Stalinist state of its nuclear weapons by fine-tuning details of how and when Pyongyang would be rewarded for its actions. The concepts remain preliminary and closely held among a small circle of negotiators, although officials told The Associated Press that one aspect involves setting out a more distinct timetable for Pyongyang to see concrete benefits for completing each phase of the denuclearization process. This could include guarantees of simultaneous action on the part of the United States and its partners such as economic and trade assistance, development aid and diplomatic recognition in return for specific North Korean steps, they said. Arranged on extremely short notice, the closed-door meeting in Beijing came as Secretary of State Condoleezza Rice was wrapping up a three-nation Asian tour during which she sought and won support from South Korea, China and Japan to jump-start the stalled process. After extensive talks on the matter in Seoul and Beijing, Rice unexpectedly ordered her top Asia hand not to accompany her to Tokyo on the final leg of the trip and remain in the Chinese capital for further consultations on fresh thoughts for overcoming the deadlock. Assistant Secretary of State Christopher Hill was to spend at least one additional day in China to flesh out ideas that Rice and Chinese President Hu Jintao discussed at length on Tuesday, officials said. "I thought it was worthwhile for him to continue those discussions," Rice told reporters in Tokyo. "Those will add to our ability to perhaps build some momentum." Rice repeatedly refused to discuss details of what was under consideration, but said all six parties to the negotiations ― the United States, China, Japan, Russia, and North and South Korea ― were looking at how to better "synchronize" the process. "It's a question of everybody moving pretty much at the same time, that would be best," she said. "We need to establish confidence in this phase that there is the prospect for real denuclearization in the next phase." Under a year-old agreement, the North agreed to shut down, disable and dismantle its main nuclear facility and provide a complete accounting for all of its atomic activities, including its transfer of technology and know-how to other countries. In return, Pyongyang's negotiating partners would provide it with fuel oil, remove sanctions, normalize relations and sign a peace regime to replace the armistice that ended the Korean war. The process has been stuck in the second phase, when the North is supposed to disable its Yongbyon facility and provide the declaration. The United States says Pyongyang has not yet produced a full and accurate declaration nearly two months after it was due. North Korea says it has, complains that it has not received promised shipments of oil, and has slowed the disabling of Yongbyon to protest, according to some accounts. Others say the slowdown is technical in nature. Nonetheless, the declaration, which was supposed to be submitted by Dec. 31, 2007, is at the crux of the current stalemate. The United States insists it provide details of North Korea's proliferation activity, including alleged sales to Syria and possibly other nations. Without that, Washington has said it is not prepared to move forward on removing North Korea from its list of state sponsors of terrorism or meet in the six-party grouping at the ministerial level, a key step toward reaching the long-term goals of the process. Frustration has been palpable and Rice's trip was designed largely to gauge prospects for success in the next 10 months as the Bush administration winds to a close. In Seoul, where she attended the inauguration of South Korea's new pro-U.S. president on Monday, Rice was buoyed by his vow to take a harder line in pressing the North on denuclearization. A day later in Beijing, Chinese officials said they shared the sense of urgency in restarting the process. She heard the same in Tokyo, where Japanese Foreign Minister Masahiko Koumura conceded that the talks were "stalled" but said his government was committed to achieving "an early submission of a complete and correct declaration." Rice's trip coincided with the historic performance of the New York Philharmonic in Pyongyang on Tuesday, an unprecedented cultural exchange between the Cold War foes. However, Rice, a classically trained pianist, played down the significance of the event, given the totalitarian nature of the North's secretive, Stalinist regime. "I heard the National Anthem played in Pyongyang. That's special," Rice said. "It's a good thing that the Philharmonic went ... but I don't think anyone should overestimate the impact on the politics of North Korea," she said.