Actor Arnold Schwarzenegger has sold a watch for $447,000 at auction after he was stopped at a German airport because of the luxury item.

The politician and star of The Terminator films, 76, remained for hours at Munich Airport during a routine check on Wednesday ahead of the auction for his environmental charity.

The Schwarzenegger Climate Initiative said on Friday the Audemars Piguet watch sold for 270,000 euros ($447,000) in Kitzbuehel, Austria, on Thursday.

In total, the sales – which also included artworks, jewellery, a personal training session with Schwarzenegger, a concert with a German band The BossHoss and a day on the set of the German-Austrian series Bergdoktor – raised 1.31 million euros ($2.16 million).

“People often ask me how I can maintain a smile when considering our environment,” Schwarzenegger said.

“It’s simple – amidst the ongoing fight against pollution, I also witness the progress that has been achieved.

“We have come a long way.

“Today, so many people are here to be part of the solution.

“We all must give back and change the world.

“Today, our supporters have played a role in creating a cleaner and healthier future.”

German tabloid Bild reported the allegedly undeclared watch was valued at about 20,000 euros ($33,000) by Schwarzenegger and was specially produced for him by Swiss manufacturer Audemars Piguet.

The Schwarzenegger Climate Initiative previously said the actor “co-operated at every step even though it was an incompetent shakedown” and that he agreed to “prepay potential taxes on the watch (remember, it is his personal watch)”.

Goods valued at more than 430 euros ($710) that will stay in the European Union have to be declared and, where appropriate, duty paid on them.

A customs penalty body in Augsburg, Germany, will evaluate the case.

Schwarzenegger, a former Republican Party governor of California, has long campaigned on the environment.

He began the Austrian World Summit climate conference, which he organises with former Austrian politician Monika Langthaler, and has vowed to “terminate pollution”.

– AAP