The Bush administration, citing evidence of progress by China to improve labor rights, announced Friday it had rejected a petition to begin a trade investigation into Chinese labor practices.

The decision turned down a request filed in June by the AFL-CIO and two members of Congress who contended the Chinese were violating international labor standards and costing 1.24 million American jobs.

In a statement issued by the office of U.S. Trade Representative Susan Schwab, the administration said engagement with China was producing evidence of real progress that labor conditions were improving in China and launching a trade investigation was not the best way to proceed.

The petition was an effort by labor groups in an election year to turn up the heat on the administration over record trade deficits the U.S. is running with China, which hit an all-time high of $202 billion last year.

"We are disappointed, but not surprised," said Thea Lee, policy director at the AFL-CIO. "The Bush administration has very little to show for its actions over the past two years."

But Sean Spicer, a spokesman for Schwab, said that pursuing a trade investigation of China's labor practices, under a provision of U.S. trade law known as Section 301, would "neither shed more light on this problem nor lead to a more effective approach for addressing Chinese workers' rights and labor conditions."

The administration said the United States had been addressing Chinese labor problems through a number of existing programs run by various agencies such as the Labor Department and the Commerce Department.

"While there remains much room for improvement, there is evidence of real progress," the administration statement said. It cited an increase in Chinese wage rates and enhanced safety inspections as a result of U.S. engagement.

The AFL-CIO was joined in the petition request by Rep. Benjamin Cardin of Maryland, the top Democrat on the Ways and Means trade subcommittee, and by Rep. Christopher Smith, R-N.J., a strong critic of China's human rights record.