The Republican governor of California, Arnold Schwarzenegger has said he will fight against any bans on gay marriage.

He surprised delegates at the San Diego at the convention of the Log Cabin Republicans, the nation’s largest gay Republican group.

Mr Schwarzenegger has previously vetoed attempts to legalise gay marriage but said he will oppose a state wide vote for a constitutional ban on gay marriage: “I will always be there to fight against that.

“I think we need a constitutional amendment so that a foreign-born (person) can run for president, but not against gay marriage. That would be a total waste of time.”

“This is extremely significant, and it’s an enormous event to have our Republican governor come out against this ballot measure, which is opposed by Democrats as well. It makes this opposition a bipartisan issue,”Geoff Kors, executive director of Equality California told the San Francisco Chronicle.

Democrat Assemblyman Mark Leno, authored a gay marriage bill that was vetoed by the governor despite its support in the California State Legislature said that Mr Schwarzenegger was “without a doubt showing leadership, and he should be applauded for it.”

“What the governor has pointed out is that even though he has not supported our marriage equality bills, one could still oppose a constitutional amendment to ban gay marriage.”