by Lorien Holland

BEIJING, Nov 20 (AFP) - US Secretary of State Warren Christopher made progress Wednesday on nuclear cooperation with China, but his intensive talks failed to remove fundamental blocks on China's human rights record and US arms sales to Taiwan.

"My intensive series of meetings reflects the importance both the United States and China attach to strengthening our relations", Christopher said after three meetings within 10 hours with his counterpart Qian Qichen, Premier Li Peng and President Jiang Zemin.

"On nuclear non-proliferation, both sides agreed to work towards an early implementation of the 1985 US-China agreement for Peaceful Nuclear Cooperation," he told a media conference.

According to high-level US aides to Christopher, China specifically agreed to develop nationwide export control systems to control the flow of weapons material and to consider joining the Zangger Committee, which is composed of countries that are nuclear suppliers and meets regularly to decide which types of technologies can be exported.

The United States has long suspected China of cooperating with Iran and Pakistan in the nuclear field, although the aides said they were optimistic that there had been no such exchange since China committed in May not to provide assistance to unsafeguarded nuclear facilities.

"If we continue to see progress in the implementation of the 1996 May agreement we can consider additional cooperation," a senior US official said.

"We are not talking about billions of dollars of hardware, but certain areas of cooperation are permissible under our current laws, for example in the nuclear safety area," he added.

Christopher also said Washington would speed up negotiations with China to allow its earlier admission to the World Trade Organisation, the official Xinhua news agency said.

Li told Christopher that delay in admitting China was "abnormal and unjust and is partly resultant from the interferance of some political factors," Xinhua said.

Christopher also said China confirmed its will to participate in four-party talks on North Korea, but there was little further agreement, with Beijing and Washington both refusing to budge on human rights and arms sales to Taiwan.

Before Wednesday's meetings began, Qian called on Christopher to cut arms sales to China's rival, Taiwan.

"China is most concerned about massive sales of advanced weapons to Taiwan. The question of Taiwan is the core issue in US-China relations," he told journalists as he began his three-hour session with Christopher.

He recalled that joint communiques issued prior to Beijing and Washington's mutual recognition included a US undertaking to gradually reduce arms sales to Taiwan.

But Christopher denied this.

"We are faithfully carrying out the commitments under the three communiques. We are assessing very carefully any arms sales to Taiwan and even though it is not called for in the communinques, this has been limited to defensive weapons," he said.

A senior US official was even blunter. When asked if Washington would agree to reduce arms sales to the nationalist island, he replied: "Of course not."

Qian also accepted Christopher's invitation to visit the United States next year, though no time was set, Xinhua said.

On human rights issues, Christopher said US objections to Chinese treatment of dissidents and the situation in Tibet were part of the "universal aspirations" of mankind.

However, Chinese foreign ministry spokesman Cui Tiankai warned that China would not accept any interference in its internal affairs, especially under the pretext of human rights.

Sino-US relations have slumped over the the past two years following a string of bilateral crises, including human rights, trade and especially over Taiwan.

But the current upturn was strong enough for Christopher to make encouraging sounds over a possible summit meeting next year between President Bill Clinton and Jiang.

"We had a good discussion of highest level meetings but I think I will save my recommendations for the President himself," Christopher said.

"I do expect this matter will be discussed between the two presidents when they meet on Sunday" at the Asia-Pacific summit in Manila, he added.

Clinton, currently visiting Australia, said Wednesday that Washington sought a deeper dialogue with China to help strengthen Asian stability, despite their differences over human rights.

"I intend to spend a lot of time, a lot of energy, a lot of effort ... but not with the view of containing the Chinese but with a view of making them a genuine partner with ourselves and others as we move forward," Clinton said.

The two countries saw their relationship hit one of its lowest points since they established diplomatic ties in 1974 erupt in March 1995 when Taiwanese President Lee Teng-Hui went to the United States on a "private" visit.