U.S. and North Korean envoys ended talks on Wednesday failing to reach an agreement on when to resume six-nation talks on dismantling Pyongyang's atomic weapons program.

U.S. Assistant Secretary of State Christopher Hill told reporters that after two days of talks with North Korean Vice Foreign Minister Kim Kye Gwan, he planned to leave Beijing on Thursday without a follow-up meeting.

A U.S. Embassy statement said that Hill's delegation "shared ideas that could help ensure progress when the six-party talks resume," without elaborating.

"The DPRK promised to study these ideas," the statement said referring to the Democratic People's Republic of Korea, the North's official name.

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Hill and Kim also met with Chinese Vice Foreign Minister Wu Dawei during the talks Tuesday and Wednesday.

The heads of delegations from the three countries met bilaterally and trilaterally, China's Foreign Ministry said in a two-sentence statement posted on its Web site late Wednesday.

They "frankly and deeply exchanged views on the issue of promoting the process of the six-party talks and improve mutual understanding," it said without elaborating. "The three parties also agreed to strive for the progress of the talks."

Hill, who had been scheduled to fly to Seoul after Beijing, canceled the trip, said Susan Stevenson, spokeswoman for the U.S. Embassy in Beijing. She did not give a reason, but said Hill now planned to leave Thursday for Washington with a possible stopover in Japan.

Meanwhile, a South Korean lawmaker claimed Wednesday that North Korea could conduct an additional nuclear test next month or early next year unless the United States offers economic concessions such as lifting financial restrictions.

North Korean leader Kim Jong Il, through an internal instruction, said his country should act as a nuclear power and it shouldn't negotiate for the sake of winning economic aid, opposition lawmaker Chung Hyung-keun said at a party meeting, according to his office.

"I believe that there are specific movements in North Korea to prepare for a second nuclear test," Chung said, citing intelligence obtained by state intelligence agencies, according to Chung's office.

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Japan's Kyodo News agency cited unidentified people at the talks as saying that Kim demanded that the U.S. lift financial sanctions and freeze U.N. sanctions that were imposed after the North's first nuclear test on Oct. 9.

Hill responded by saying that the possible lifting of financial sanctions can be discussed during the talks and working level discussions, which are expected to be held simultaneously, Kyodo said.

Similar stances were taken when the three met bilaterally and trilaterally on Tuesday, Japanese and South Korean media have reported.

While in Beijing, Hill also met with South Korea's nuclear envoy, Chun Yung-woo, and Japan's representative Kenichiro Sasae.

Prime Minister Shinzo Abe told reporters in Tokyo on Wednesday evening that Foreign Minister Taro Aso had updated him on the status of preparations aimed at resuming the six-party talks, but declined to offer details.

The prime minister also stressed that resuming the talks was a means toward an end, not an end in and of itself.

"The objective is not to resume six-party talks," Abe said. "Our efforts are aimed at holding six-party talks that produce results."

North Korea agreed in September 2005 to abandon its nuclear program in exchange for security guarantees and aid. But Washington imposed the financial sanctions against a Macau-based bank on suspicions it was laundering counterfeit money for the North Koreans. Angered by the move, Pyongyang withdrew from the talks two months later.

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Officials have yet to set a date for the next round of negotiations. The China-hosted talks involve the United States, North Korea, Japan, South Korea and Russia, which has not sent an envoy to Beijing.

U.S. State Department spokesman Sean McCormack said in Washington that the main goal of the current meetings was to "make sure that everybody, at least, has a good, solid understanding of what might happen" when the six-nation talks resume.

Kim said earlier this week that the timing of the next round of six-nation talks "depends on the United States."

Kim's trip to Beijing — a rare overseas visit — and the presence of other negotiators had lifted expectations that there could be a breakthrough in ongoing efforts to restart the talks.

An unannounced meeting between Hill and Kim last month in Beijing led to Pyongyang agreeing to return to the arms negotiations amid heightened tensions after the Oct. 9 nuclear test.

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