The first Terminator movie appeared in 1984

"My client never gave those rights that his photo could be used and has never consented to the use of his voice," said the actor's lawyer, Marty Singer.

Mr Singer said Schwarzenegger is seeking $20m (�13.5m) in damages, which is the amount he believes he would have received had he approved the use.

In the Terminator films, Schwarzenegger plays a cyborg warrior who is sent back from the future to prevent the birth of a future resistance leader.

IGT spokesman Rick Sorensen said the Reno-based company was producing the Terminator games under licences with French TV's Canal Plus, which belongs to media giant Vivendi.

But Mr Singer said that third parties were not allowed to use actor's voices or likenesses without express permission.

IGT is the US's largest slot-machine maker, accounting for more than 50% of the market and with a turnover of $1bn (�678m) last year.

Austrian-born Schwarzenegger's new film Collateral Damage has been withdrawn indefinitely after the attacks on the US forced Hollywood to re-examine movies with violent or terrorist themes.

Schwarzenegger took US citizenship in 1983 and is a strong supporter of the Republican party.