China’s vice premier said China will continue to open its economy, but he urged the United States to avoid protectionism and share technology on energy and climate change.

“A trend of protectionism has emerged in the United States, a country based on free trade," Wang Qishan said at a reception Thursday in New York. “The United States should not close its doors or practice protectionism. The US should continue to be an open country."

Wang’s comments followed high-level economic talks this week in which China and the United States pledged greater cooperation to boost bilateral investment and deal with energy shortages and climate change.

The two countries agreed to launch talks on a treaty that could allow more US investment in China’s booming economy—a major initiative of the Bush administration.

The agreements on energy, the environment and investment followed two days of talks aimed at diffusing simmering economic tensions.

Wang said China would continue down the path of economic reform, noting recent efforts to strengthen intellectual property rights, boost food and product safety, and protect foreign investors. But he urged patience as the developing Asian country of 1.3 billion people seeks to modernize its economy, poised to surpass Germany to become the world’s third largest after the US and Japan.

“We are making efforts to build institutions and a sound legal framework," said Wang, a former mayor of the Chinese capital, Beijing.

“There is still much room for improvement," he added. “We need to improve transparency, but (the US) should recognize how much progress China has made. We have done in 30 years what it took America 100 years to do.

Wang spoke at a dinner reception at a posh New York hotel. Guests included former US Secretary of State Henry Kissinger, former US ambassador to the United Nations, Richard Holbrooke, and Morgan Stanley Chief Executive John Mack.

Calling US-Chinese relations of “paramount importance," Wang urged the United States to share more technology to prevent climate change and boost energy efficiency. He noted China could use US expertise to capture carbon emissions from coal-fired power plants—a chief source of global pollution.

“This area of capturing carbon emissions enjoys broad prospects and wonderful business opportunities," Wang said.

He noted that US firms have been reluctant to share technology with China because of lax intellectual property laws, but he said he pledged to work on the problem in talks with Treasury Secretary Henry Paulson.

The talks were the fourth round of a series of negotiations known as the Strategic Economic Dialogue.