The two sides are at odds over agricultural and financial services regulation, among other restrictions.
Turning to China, Froman said he saw encouraging signs for bilateral relations as China's new leadership grapples with serious economic issues such as deciding whether it wants to rely so heavily on export-led growth to questions about air pollution and food safety.
"China agreeing to start negotiations on a bilateral investment treaty ... is a potentially very important development and could help drive reform in China," Froman said.
China agreed to negotiate the treaty during annual U.S.-China security and economic talks in Washington earlier this month. The U.S. has been pushing for such a treaty for years, saying it would facilitate more protections and market access for American investors in China, where state-owned company enjoy many competitive advantages.
China's new leader, Xi Jinping, who met President Barack Obama last month in California, has signaled he intends to shift toward an economy driven more by domestic consumption and less by exports — changes that would benefit U.S. companies that want to sell products and services to China's fast-growing middle class.
Regarding Japan's recent entry into the Trans-Pacific Partnership trade negotiations, Froman said it was critical that the country resolve longstanding issues over opening its markets to American products — particularly barriers to U.S. autos, farm products and insurance services. In 2010, for example, the United States exported about 14,000 vehicles to Japan, while importing some 1.5 million vehicles.
Japanese Prime Minister Shinzo Abe has said that he is prepared to expose his country's sheltered industries to more foreign competition, but he faces strong resistance from many in his own party.
Talks on the trade deal began more than two years ago and Japan just joined 11 other participants — Australia, Brunei, Canada, Chile, Malaysia, Mexico, New Zealand, Peru, Singapore, the U.S. and Vietnam. With Japan, it would be the largest free-trade agreement ever, including countries that make up about 40 percent of world trade.