WASHINGTON - President Barack Obama will launch a new trade enforcement case against China on Monday, using the power of incumbency to counter Republican Mitt Romney's criticism that he is ceding American jobs to the Asian power.

Senior administration officials said the president will announce the new case, targeting Chinese subsidies for exports of automobiles and automobile parts, Monday during a campaign trip to Ohio. The swing state has a large manufacturing base where many blame China for depressing its industry.

The winner of the U.S. presidential election is not determined by national popular vote, but by a series of state-by-state contests, making victory in battleground states such as Ohio and Florida particularly important.

Obama and Romney have both pushed China — and through it, the economy — to the forefront of the White House race as they seek to refocus after a week dominated by foreign policy and the turbulent events at U.S. embassies throughout the Middle East.

Romney has accused Obama of being weak on China to the detriment of U.S. workers. The president countered with claims that Romney has investments in Chinese companies and outsourced jobs to China while running the private equity firm Bain Capital.

On Monday, with both candidates returning to the campaign trail after a weekend out of the spotlight, Obama will try to gain the upper hand in the debate.

Officials said the administration will launch enforcement action at the World Trade Organization because it says China is illegally subsidizing exports in their autos and auto parts sectors. The U.S. says the practice puts American parts manufacturers at a competitive disadvantage and encourages the outsourcing of production to China.

The officials requested anonymity because they were not authorized to discuss the trade action publicly ahead of the president.

The administration is taking the issue to the WTO because its attempts to get China to address the subsidies on its own have been unsuccessful, the officials said.

Jobs in the U.S. auto parts sector dropped by roughly half between 2001 and 2010, while U.S. imports of auto parts from China have increased seven-fold, according to the Obama administration.

The administration is also escalating another case it brought against China at the WTO in July that accuses China of imposing unfair duties on more than $3 billion in exports of U.S. autos. The duties cover more than 80 per cent of American auto exports to China, said the officials.

The cases stem from the Interagency Trade Enforcement Center Obama set up earlier this year to target unfair practices around the world, particularly in China.

Obama and Romney started trading barbs on China late last week.

Romney released a television advertisement Thursday accusing Obama of "failing American workers" and ignoring unfair trade practices by China. And in his weekly podcast Saturday, Romney said: "In 2008, candidate Obama promised to take China 'to the mat.' But since then, he's let China run all over us."

Obama countered with a TV spot focused on its claims that Romney outsourced jobs to China while working in the private sector. Obama's campaign also released a new web video Saturday in which deputy campaign manager Stephanie Cutter said Romney holds investments in Chinese companies.