The Commerce Ministry said it would look into complaints that American auto and chicken products are being dumped into the Chinese market or are benefiting from subsidies. The ministry said there are concerns the US imports have "dealt a blow to domestic industries."

The ministry statement did not elaborate on the complaints or how the investigation would proceed.

Washington and Beijing have recently traded accusations of protectionism, which they agree will hurt efforts to end the global economic crisis.

The Commerce Ministry's statement said China remained firmly opposed to protectionism.

"Since the financial crisis, China's actions have proven this point," it said. "China is willing to work with countries around the world to act together to promote the quick recovery of the world economy."

China and the US banned each others' poultry in 2004 following an outbreak of bird flu in Asia. But China lifted the ban after a few months and has complained that Washington refused to do the same.

Since then, China has imported more than four million tons of US poultry - mostly feet and other parts that are popular in China but not elsewhere.

The World Trade Organization launched an investigation of the US ban on Chinese poultry at the end of July. Beijing told the WTO's dispute settlement body that Washington had imposed protectionist measures in completely banning Chinese chicken products entering the US market. The United States said it was still examining whether Chinese poultry was safe for human consumption.