BEIJING, Nov 23, 2007 (AP) -- China's top trade envoy tried Friday to dispel complaints that Beijing is restricting foreign investment to protect its companies, insisting the country is "open forever" to capital from abroad.

The remarks by Vice Premier Wu Yi, the envoy to strategic economic talks next month with Washington, follow complaints by foreign companies that China is limiting investment in key industries in violation of free-trade pledges.

"Some American friends are worrying about whether China will shrink its opening up policy and change its attitude toward foreign capital," Wu told an audience at an American Chamber of Commerce in China dinner.

"The position of the Chinese government to value FDI (foreign direct investment) and attract more foreign capital won't change," she said, prompting loud applause. "China's door will be open forever."

Complaints about investment barriers are expected to be on the agenda at the Dec. 12-13 meeting of the U.S.-Chinese Strategic Economic Dialogue led by Wu and Henry Paulson, the U.S. Treasury secretary.

Wu mentioned no new initiatives Friday but stressed the benefits for the United States of trade with China, a source of inexpensive goods and markets for American companies.

"The Chinese economy will generate rich profits for American companies," Wu said.

Wu, 69, is the highest-ranking woman in China's leadership, and is widely admired by foreign businesspeople as a champion of free trade.

She confirmed Friday that she will give up her official posts when a new government takes office next year. Wu stepped down last month from the ruling Communist Party's Central Committee.

"I will retire and not hold any positions anymore," she said.

Forbes magazine listed Wu this year as the world's second-most powerful woman, behind German Chancellor Angela Merkel and ahead of U.S. Secretary of State Condoleezza Rice.