TACOMA, Wash. (AP) — U.S. Treasury Secretary Tim Geithner visited some of the top exporters in Washington state on Tuesday in advance of a trip to encourage China to open more of its markets to American companies and their products.

After going to Boeing Co.'s 737 jetliner plant in Renton, Geithner and Gov. Chris Gregoire dashed through an abbreviated tour of the Port of Tacoma during a drenching rain. After glancing at a line of tractors and other heavy vehicles destined for China, they watched a rapid parade of large container-moving equipment before retreating to their cars.

Geithner also spoke in Tacoma to a gathering of community bankers, then headed to Redmond for Microsoft Corp.'s annual CEO summit.

With and Seattle and Tacoma as major ports, and billions of dollars in foreign sales by aircraft, software, agriculture and other industries, Washington bills itself as the most trade-dependent state and counts China among its fastest-growing markets. Geithner, with nods from Democrat Gregoire, touted the administration's trade and economic policies and said any improvement it makes in China relations will directly benefit the state.

U.S. Commerce Secretary Gary Locke, Washington's governor before Gregoire, is currently on a trade mission in China. He is to be joined in Beijing by Geithner, Secretary of State Hillary Rodham Clinton and U.S. Trade Representative Ron Kirk for the Strategic Economic Dialogue, an annual meeting for the two countries to air disagreements on trade, currency and other policies.

Geithner, who also was in Beijing last month, said that after decades of relying on exports for its economic growth, China is promoting more consumption and imports by its people. That will further expand a critical U.S. market, but the administration wants policy changes to ensure U.S. companies aren't shut out in favor of Chinese producers.

The U.S and other Chinese trading partners also say China's currency is being kept undervalued, giving its exporters an unfair price advantage.

"I think it's, of course, China's decision about what to do with the exchange rate — they're a sovereign country," Geithner said. "But I think it's enormously in their interest to move, over time, to let the exchange rate reflect market forces, and I'm confident that they will do what's in their interest."

The U.S. also wants stronger intellectual property protections by the Chinese, and again Geithner said it's to their benefit.

"They want to make sure they're supporting their scientists, their engineers and innovators and you cannot do that without providing better protections for intellectual property," he said.