TOKYO, Japan (AP) -- U.S. Secretary of State Condoleezza Rice has ordered her top Asia diplomat to stay in China to look at fresh ways of unblocking the stalled effort to get North Korea to abandon nuclear weapons, her spokesman said Wednesday.

Rice instructed Assistant Secretary of State Christopher Hill to remain in Beijing to study with Chinese officials new ideas of moving the process ahead, instead of accompanying her to Japan.

"She asked him to stay back, and (he is) working on the six party talks with the Chinese," State Department spokesman Sean McCormack told reporters onboard Rice's plane en route to Tokyo from Beijing.

McCormack said Hill was working on proposals put forward by Rice and Chinese President Hu Jintao on Tuesday to jump start the multinational denuclearization efforts that include the United States, Japan, Russia, China, North Korea and South Korea.

"We came with ideas, they had some ideas. Let's see if we can tease some of these ideas," McCormack said, adding that the atmosphere between Rice and Hu had been "very good."

"We'll see if it leads somewhere," McCormack said. He would not discuss details of the ideas under consideration.

Rice said Tuesday that China and the U.S. were looking at ways to "synchronize" the actions the North must take to meet its obligations, and the benefits it is to receive for those measures.

Hill had planned to travel with Rice on all three legs of her Asian tour that has been dominated by the North Korea issue. She has visited South Korea in addition to China and Japan.

The unexpected cancellation of Hill's presence in Japan, a major U.S. ally in Asia, to work with the Chinese may herald significant developments.

Hill does not plan to meet directly with North Korean officials during his extended stay in Beijing, where he will be for at least another day, McCormack said.

On Tuesday, Rice won assurances from China that it would use its influence on North Korea to help with the denuclearization process.

In broad discussions with Chinese officials, Rice also won an agreement from China to resume an on-again, off-again human rights dialogue with the United States and she pleased her Chinese hosts by restating firm U.S. opposition to a Taiwanese referendum on United Nations entry that has infuriated Beijing.

But North Korea dominated the talks. Rice urged China, which has considerable leverage with its Stalinist neighbor, along with others in the six-nation denuclearization effort, to "use all influence possible" with Pyongyang to meet its pledges to the group.

"I believe that all of the parties to the six-party talks have both an obligation and an interest to make certain that the obligations of the first phase are carried out," Rice told reporters at a news conference with Chinese Foreign Minister Yang Jiechi.

"We are (at) the cusp of something very special here," she said, referring to the shutdown and continuing disablement of North Korea's main nuclear facility in Yongbyon. "Now it is time to move on because the denuclearization of the Korean peninsula is in everyone's interest."

"What I am expecting from China is what I am expecting from others: Use all influence possible with the North Koreans to convince them that it is time to move forward," Rice said.

Yang said China was "consistently committed to the six-party talks and the denuclearization of the Korean peninsula" and would continue to work on the matter. But he also made clear that Beijing had already pressed the North hard on the matter.

"The Chinese side hopes that the parties will treasure the results we have already produced, which have not come easily," he said.

Speaking later after extensive discussions with Chinese President Hu Jintao, Rice said she was pleased with the Chinese stance. "I think China shares our desire to get this moving forward at a more rapid pace, and I know they are using their good offices to try to do so," she said.

Although progress has been made in disabling Yongbyon, the United States says North Korea has not yet produced a full declaration of its nuclear programs, including details on the transfer of technology and know-how that could be used to develop atomic weapons.

The declaration was due almost two months ago, and the North says it has already met the requirement. However, the Bush administration rejects the claim, which has slowed progress on the process aimed at restoring stability in North Asia and bringing a final end to the Korean War.

Yang said China was eager to see the second phase of the denuclearization process -- the complete dismantlement of Yongbyon, the production of the declaration and in return the provision of fuel oil to North Korea -- completed quickly.

In Beijing, Rice said she had also raised human rights issues, along with intellectual property protections, product safety, efforts to impose new sanctions on Iran over its nuclear program and the upcoming referendum in Taiwan. Beijing sees the island as a breakaway province.

Yang said China had agreed to resume the human rights dialogue with the United States that it had broken off in 2004 when the Bush administration unsuccessfully sponsored a resolution censuring China before the U.N. Human Rights Commission. He did not, however, give a date.