soon. «When the talks resume we will focus our negotiations on this issue.» The dispute erupted in late 2002 after U.S. officials said the North admitted violating a 1994 deal by embarking on a secret uranium enrichment program. Pyongyang later withdrew from the international Nuclear Non-Proliferation Treaty. In February, the North claimed it had nuclear weapons. Hill met Saturday with Chinese and North Korean officials in what he said was an attempt to find ways to speed up the negotiations, but he said the meeting made little progress. Hill on Friday challenged the North's insistence on retaining a peaceful nuclear program, pointing to its record of converting a research reactor for weapons use. He was referring to the North's main nuclear complex at Yongbyon, purportedly built for research with Soviet assistance but later turned into the headquarters for the North's nuclear weapons program. North Korean leader Kim Jong Il has said his isolated government would rejoin the non-proliferation treaty and admit international inspectors if the Beijing talks are successful.