Delegates to talks on disarming North Korea's nuclear program voiced their impatience Wednesday that the negotiations remained stalled over a dispute on when US$25 million of Pyongyang's funds will be released from a Macau bank. North Korea said it would not take part in the six-party negotiations in China's capital to meet goals outlined in a landmark Feb. 13 disarmament agreement until the money is transferred. At least one envoy expressed his frustration at the lack of progress. "Today is the last day," Chun Yung-woo, South Korea's representative told reporters. "I don't know why we should waste our time waiting for the obstacle to be cleared," He said the delegation was considering leaving if the situation did not change, adding that "there is no realistic method to convince North Korea to take a practical attitude." Planned group talks were called off on Tuesday, with some participants holding bilateral meetings instead, after North Korea said it would not take part until the money was in its account. A session for chief envoys was planned Wednesday afternoon but it was not immediately clear if it would convene. North Korea boycotted the six-nation talks for more than a year after Washington blacklisted the tiny, privately run Banco Delta Asia on suspicion the funds were connected to money-laundering or counterfeiting. But US officials announced Monday that the money would be transferred to a North Korean account in Beijing, saying it was up to the Monetary Authority of Macau, a Chinese territory, to release the funds. Chun said the transfer has run into "minor technical problems," but he did not give any details. The authority has declined to say if it will announce when the funds have been released. "I have no instructions from my superiors regarding when the money will be transferred," Wendy Au, a spokeswoman for the authority, said Wednesday. Banco Delta Asia spokesman Joe Wong said the money remains frozen and that the Monetary Authority hasn't ordered the bank to release the funds. Despite the growing tensions, Japan's chief delegate, Kenichiro Sasae, said he was still optimistic of progress once the transfer dispute was resolved. "As soon as the current problem, which is a technical issue, is resolved, I believe things will start moving forward," he told reporters. "I hope talks among the heads of the delegations will resume, paving the way for progress on the discussions on the denuclearization issue," he said. The setback comes as the two Koreas, the US, Japan, Russia and host China are trying to fine-tune a timetable for North Korea's disarmament under the February agreement. Under the deal, North Korea is to receive energy and economic assistance and a start toward normalizing relations with the US and Japan, in return for beginning the disarmament process. North Korea would ultimately receive assistance equivalent to 1 million tons of heavy fuel oil if it fully discloses and dismantles all its nuclear programs. The Chosun Sinbo, a pro-North Korea paper in Japan, said the North Korean "delegation is maintaining a position that returned funds should be directly confirmed in order for the BDA issue to be finally resolved." The negotiations have also been complicated by Pyongyang's strained ties with Tokyo. North Korea is upset at Japan's insistence that the two nations settle issues related to Pyongyang's abduction of Japanese citizens in the 1970s and '80s before taking steps to improve relations.