DETROIT, Michigan — Chrysler's chief on Tuesday joined a chorus of critics slamming Mitt Romney for an ad that implies Jeep is shipping American jobs to China as a result of President Barack Obama's policies.

The ad is airing in the critical battleground of Ohio, where one in eight jobs depends on the auto industry and Chrysler is building Jeeps at a plant in Toledo.

It was produced after the Republican White House hopeful was roundly criticized for telling supporters in Ohio last week that Jeep was going to move "all" production to China.

Chrysler called the rumor "a leap that would be difficult even for professional circus acrobats."

Obama won a lot of support among Ohio's blue collar workers by pushing through an $84 billion bailout of the US auto industry despite objections from Republicans -- including Romney, who has taken heat for declaring "let Detroit go bankrupt" in the midst of the crisis.

With just a week to go before the November 6 election, Obama is currently up by 2.1 points in a Real Clear Politics average of recent Ohio polls.

Romney's ad shows cars being crushed as a narrator declares that "Obama took GM and Chrysler into bankruptcy and sold Chrysler to Italians who are going to build Jeeps in China," while insisting Romney will "do more" for the auto industry.

Chrysler chief executive officer Sergio Marchionne insisted that plans to build Jeeps in China are a sign of the company's strength and that local production is the only way to expand in the world's largest automotive market.

He also noted that Chrysler has tripled Jeep production in the United States and added more than 11,200 jobs since it came under Fiat's stewardship in 2009. "Jeep assembly lines will remain in operation in the United States and will constitute the backbone of the brand," Marchionne said in a letter to employees.

"It is inaccurate to suggest anything different."

The Obama campaign fought back Monday with an ad of its own calling Romney "wrong then... dishonest now," interspersed with a clip of Romney saying "let Detroit go bankrupt."

Romney has called his rival's use of the quote misleading, insisting that that he was simply saying the private sector should take the lead and that Obama ultimately did as he suggested by restructuring General Motors and Chrysler under bankruptcy protection.

Critics and experts have noted that credit markets were essentially frozen due to the financial crisis and that GM, Chrysler and their suppliers would have simply collapsed without government help at a cost of about a million jobs.

Both companies have posted huge profits, expanded production, added jobs and repaid most of their loans since emerging from the government-backed bankruptcy.