(Reuters) - "Dirty Harry" star Clint Eastwood will bring a touch of Hollywood glamour to the Republican National Convention on Thursday, jetting in as a surprise last-minute speaker to warm up the crowd for presidential candidate Mitt Romney, the CNN and Fox networks reported.

The Academy Award-winning actor and director endorsed Romney earlier this month, appearing at a fundraiser for him in Idaho.

Eastwood was reluctantly drawn into the 2012 campaign earlier this year when an ad by Chrysler, titled "Halftime in America," ran during halftime of the Super Bowl, narrated by Eastwood.

Many people thought it might have been an endorsement of President Barack Obama because Chrysler received a government bailout.

At the time, Eastwood said flatly that he was not endorsing either candidate, telling Fox he is "certainly not politically affiliated with Mr. Obama."

(Reporting by Claudia Parsons; Editing by Jim Loney)