President Clinton and Chinese President Jiang Zemin, in a summit heavy on symbolism, are looking to achieve some substance, too.

Although Clinton administration officials have publicly sought to hold down expectations for dramatic agreements, the United States is pressing China to take more measures to halt the spread of missile technology and nuclear, chemical and biological weapons - from the Indian subcontinent to the Korean Peninsula. It's part of a "constructive strategic partnership" the two leaders say they want."China will either be part of the problem or part of the solution," Clinton said this week, laying the ground for the Saturday summit.

For Jiang's part, he said China under his leadership will work more closely with the United States despite deep differences over human rights, illustrated with a roundup of dissidents at the outset of Clinton's visit. Clinton aides said the president would press the matter in his Saturday summit.

Clinton, in his meeting with Jiang, was expected to urge Chinese authorities to release political prisoners.

The president also will urge China to talk directly with Tibet's exiled spiritual leader, the Dalai Lama, on autonomy for the region.

China, on the other hand, sees Taiwan's future as its No. 1 priority, and Jiang will urge Clinton to reiterate that the United States doesn't want to see an independent Taipei government.

Putting aside differences, the two presidents will focus on how the United States and China can work together to ensure stability in a region rocked by nuclear tests from India and Pakistan and an Asian financial crisis. For decades, Beijing helped Islamabad's nuclear program, but in just the past couple years has agreed to stop, including halting delivery of missiles to Pakistan. China also has halted cooperation with Iran.

Now, the Clinton administration wants China to stop exporting all missile-related technology and know-how to Pakistan and Iran as well by agreeing to adhere to all aspects of the Missile Technology Control regime.

Improved Chinese export controls on chemical and biological materials to prevent their use as weapons also are on the agenda.

Negotiations continued through the eleventh hour, said Stanley Roth, assistant secretary of state for the region.

"The whole agenda is aimed at strategic cooperation," Roth said.

As an example, Clinton and Jiang will discuss pushing harder for successful four-party peace talks among North and South Korea, China and the United States, Roth said. China played a key role in getting North Korea to freeze its nuclear weapons program in 1994.

China, one of five declared nuclear powers, has 13 nuclear-tipped missiles aimed at U.S. cities and has been discussing detargeting them as a goodwill gesture, too. Beijing wants the U.S. government to pledge that it would never be the first to use nuclear weapons, however, and Berger reiterated Friday that the Clinton administration would not make such a promise.

On other issues, the two presidents will likely agree to step up U.S. training of Chinese judges and lawyers and establish ways to reduce environmental pollution in China. Agreement also is likely on cooperative approaches to health issues.