BEIJING - Chinese and U.S. trade officials downplayed their countries' differences yesterday, saying both sides needed to fend off protectionism as they prepared for difficult negotiations on economic disputes that include exchange rates and product safety.

The talks come amid anger in the U.S. Congress over China's massive trade surplus and demands by some members that Washington act forcefully to compel Beijing to halt what they see as currency manipulation and other unfair trade practices.

Discussions are set to begin today with a one-day meeting of the China-U.S. Joint Commission on Commerce and Trade, which deals with near-term regulatory and legal issues.

That is scheduled to be followed tomorrow and Thursday by the third round of the Strategic Economic Dialogue, which grapples with longer-term economic plans. Vice Premier Wu Yi, a former chief trade negotiator, leads the Chinese side.

In remarks at a seminar on innovation in Beijing, U.S. Commerce Secretary Carlos Gutierrez acknowledged protectionist pressures in both the United States and China.

"We have to continue opening global markets. America and China must work together to stem the tide of protectionist sentiment in our nations," Gutierrez said.

In an interview with the official English-language China Daily newspaper, Chinese Vice Commerce Minister Chen Deming stressed the rising interdependence of the U.S. and Chinese economies and warned their trade could be harmed by focusing too much on the value of the yuan and on intellectual-property rights.

U.S. Health Secretary Mike Leavitt was to sign agreements in Beijing today on food and feed-product safety and on drugs and medical devices.

U.S. Treasury Secretary Henry M. Paulson Jr., U.S. Trade Representative Susan Schwab, and acting Secretary of Agriculture Charles Conner are also taking part in the talks.