U.S. President Barack Obama on Monday touted his administration's newly filed enforcement case against China at a campaign event in Ohio, trying to outplay Republican challenger Mitt Romney in "a good game" of taking a tougher stance on China.

Obama (L) VS. Romney [Photo/agencies]

"I understand my opponent has been running around Ohio claiming he is going to roll up his sleeves and he's going to take the fight to China," said Obama to thousands of supporters in Cincinnati.

"You can talk a good game, but I like to walk the walk, not just talk the talk," said the incumbent, following recent barbs that he and Romney have traded each other less than two months ahead of the November showdown.

U.S. presidential candidates often have the bad habit of playing a blame-China game in election years.

Chinese officials have repeatedly urged U.S. politicians to view China's development in an objective and rational way, stop making groundless accusation against China and contribute more to China-U.S. mutual trust and cooperation.

Earlier on Monday, U.S. Trade Representative Ron Kirk announced that the federal government had brought a case against China to the World Trade Organization (WTO), requesting for consultations with China on its measures providing "extensive subsidies" to auto and auto-parts producers located in designated regions, known as "export bases."

The Obama administration official alleged that those "export bases" had made at least 1 billion U.S. dollars in subsidies available to auto and auto-parts exporters in China during 2009 to 2011, giving its manufacturers an advantage over U.S. producers.

The administration's latest enforcement action will have "particular resonance in the state of Ohio, where the auto-parts sector employs more than 54,000 people directly, and where the auto industry as a whole supports 850,000 jobs in Ohio," said Josh Earnest, a White House spokesman during a press gaggle aboard Air Force One en route Ohio.

Asked whether the announcement was brought to coincide with China becoming a campaign issue recently, Earnest insisted that the announcement has been in the making for months, and the president was not focused on the politics.

However, Earnest explained that the reason why Obama touted the action in a political event instead of an official event was that the president had to balance his responsibilities both as the president and as a candidate on a close presidential race.

"This is something you can expect to hear the president continue to do over the course of the next 50 days," said the spokesman.

Romney fired back in a Monday statement calling the Obama administration's trade lawsuit a "campaign season" move.

"Campaign-season trade cases may sound good on the stump, but it is too little, too late for American businesses and middle-class families," wrote the statement.

The Romney campaign has denied criticism of his opponent tagging the former Massachusetts governor and CEO of Bain Capital as a "pioneer" of outsourcing American jobs.

Romney, who promised to designate China as a currency manipulator on the first day of office if elected, has repeatedly blasted Obama for failing to punish China.

In an article released online on Monday, The New York Times reported that "bashing China is a tried-and-true campaign strategy for both parties, particularly in swing states like Ohio" that have seen heavy loss of manufacturing jobs.

Before the administration's new move, The Wall Street Journal last Saturday criticized Romney for playing protectionism in a campaign ad that slams Obama for failing to stop the so-called "China's cheating."

The latest campaign ad, entitled "Failing American Workers," signaled that 582,000 U.S. manufacturing jobs have been lost to China since Obama became president. It claimed that, for the first time, "China is beating us" as the world's leading manufacturing country.

Romney's "China-bashing" is especially odd for the candidate, because he "professes elsewhere that he wants to expand trade because it will create jobs," The Wall Street Journal said in an article, noting that China is a major trade partner of the United States.

"As a former businessman, Mr. Romney surely knows that cheaper Chinese imports create jobs in the U.S. up and down the merchandise and services value chain," the article said, referring to a recent Heritage Foundation study that finds that the imports from China support nearly 600,000 American jobs in the apparel and toy industries alone.

The Chinese government has repeatedly urged the United States to abide by its commitment against protectionism and maintain a free, open and just international trade environment.

On Monday, China requested to negotiate with the United States over countervailing duties levied by Washington against Chinese tyres within the trade dispute settlement mechanism of the WTO.

"Through consultations within the WTO trade dispute settlement mechanism, the Chinese side hopes the U.S. can correct its wrong-doing and properly deal with concerns from China," said Shen Danyang, a spokesman for the Chinese Ministry of Commerce.