A US industry and union coalition accused China Tuesday of sweeping illegal subsidies to its auto parts sector that threaten to destroy more than a million US jobs.

Launching a campaign to press for trade action against Beijing, the Alliance for American Manufacturing and senior politicians said the Chinese subsidies threaten to reverse the comeback of the US auto industry.

The AAM -- which brings together the US steel industry and the United Steelworkers union -- said alleged trade violations by China have already killed 400,000 jobs in the US auto supply chain, and threaten 1.6 million more.

"It's essential that federal action be taken to challenge these abuses before they completely undermine the job recovery under way in the US auto industry," said AAM executive director Scott Paul.

The campaign was launched at the US Congress a week after President Barack Obama said he would step up pressure on China and other countries that unfairly subsidize exports and launch a new government body to pursue such cases.

The AAM released three reports that paint China as targeting the US auto parts sector by supporting its own manufacturers in ways that violate WTO fair trade rules.

A report by Usha Haley of the Economic Policy Institute said China now sends about one-third of its auto parts production to the United States.

The study said China subsidized the sector to the tune of $27.5 billion since 2001, and has committed nearly $11 billion more in subsidies over the next decade.

"In auto parts, China runs trade deficits with every other major auto producer, including Japan, South Korea, and Germany. In contrast, Chinas trade surpluses on auto parts with the United States constitutes a notable exception," Haley said.

But Haley also blamed US auto makers themselves for sourcing more parts from China rather than at home.

Senator Sherrod Brown, who represents Ohio, home to many US auto parts makers, said the Obama administration needed to push back at China to protect US jobs and industry.

"We know that aggressive trade enforcement pays off," Brown said at the launch of the campaign at the US Capitol.

"It's important to stand up to China," he said. "It's good for workers, it's good for manufacturers."