Sacramento - California governor Arnold Schwarzenegger urged opponents of California voters' ban last week on gay marriage to keep fighting and indicated his hope that state courts would step in to overturn it.

The statements to CNN marked the clearest comments by the Republican leader of the largest state in the US. The former movie star also predicted that the 18,000 gay and lesbian couples who have already wed would not see their marriages nullified by the initiative.

"It's unfortunate, obviously, but it's not the end," Schwarzenegger said in the CNN interview Sunday. "I think that we will again maybe undo that, if the court is willing to do that, and then move forward from there and again lead in that area."

Previously Schwarzenegger fudged his views on the issue, rejecting legislation authorizing same-sex marriage and saying that he believes that marriage should be between a man and a woman. However he has also said he would not care if same-sex marriage were legal, and publicly opposed Proposition 8, which amends the state constitution to declare that "only marriage between a man and a woman is valid or recognized in California."

Schwarzenegger also urged backers of gay marriage to follow the lesson he learned as a bodybuilder trying to lift weights that were too heavy for him at first. "I learned that you should never ever give up ... They should never give up. They should be on it and on it until they get it done."

Schwarzenegger's comments came after thousands of protestors held demonstrations Sunday outside churches that had been among the strongest backers of the gay marriage ban.

The amendment was passed by 52 to 48 per cent of voters in last Tuesday's election but has since been challenged by three law suits that claim it unconstitutionally discriminates against gay people. (dpa)