SAN FRANCISCO -- Opponents of gay marriage asked the California Supreme Court on Wednesday to block San Francisco from issuing any more same-sex marriage licenses and to nullify the thousands of weddings already performed.

The suit was filed by the Alliance Defense Fund after two state judges declined to prohibit San Francisco city officials from continuing to sanction the same-sex marriages, more than 3,300 of which have been performed at City Hall since Feb. 12.

Robert Tyler, an attorney for the Alliance Defense Fund, said "we would have complete chaos in the system" if local officials are allowed to declare what is state law and what is not.

San Francisco's gay marriage spree continued Wednesday under orders from Mayor Gavin Newsom, who says he's following the California Constitution's equal protection clause, which demands that all people be treated equally. Newsom also says California's marital law banning same-sex marriages is unconstitutional.

On Tuesday, President Bush cited San Francisco's gay marriages as well as a recent ruling by Massachusetts' highest court when he backed a constitutional amendment banning same-sex marriages.

California Attorney General Bill Lockyer has said he will ask the state Supreme Court on Friday to intervene in a countersuit San Francisco has brought against the state.

Lockyer has said that he personally believes San Francisco is violating state law, but that the high court should decide the controversy.

Conservative groups have said they do not trust Lockyer, a leading Democrat and potential rival to Gov. Arnold Schwarzenegger in the 2006 election, to strenuously defend their position. On Tuesday, several Republican politicians said they would launch a campaign to have Lockyer recalled from office. Lockyer said he was unfazed by the criticism, which he said was "just part of my job."

The Alliance Defense Fund argues that the California Constitution does not grant Newsom the authority to issue the licenses in contravention of state laws defining marriage as a union between a man and a woman.

But the constitutionality of same-sex marriages is not at issue in the case filed Wednesday, which merely asks the justices to declare that Newsom lacks the power to direct San Francisco Clerk Nancy Alfaro to issue the licenses.

"This latest appeal is about politics, not the law," said Jon Davidson, senior counsel for the Lambda Legal Defense and Education Fund, which intervened on behalf of five couples who have wed in San Francisco or plan to get married.

"Anti-gay groups that have already begun attempts to recall the attorney general are racing ahead of him to the state's highest court in an effort to score political points," Davidson said.

The court did not indicate whether it would even hear the case, let alone immediately act to block the city from issuing the licenses.

"I think we're a long way for final resolution to this," said Gerald Uelmen, a Santa Clara University School of Law scholar who closely follows the state's top court.

The constitutional issue could be resolved when California's courts look at Newsom's lawsuit against the state, or if gay couples sue for a marriage license in cities outside San Francisco. Massachusetts' highest court has sanctioned same-sex marriages in a case involving a gay couple seeking a marriage license there.

California's justices usually are loathe to take cases until they work their way up through the lower courts, which this case has not done.

But the alliance wants the court to immediately intervene because the issue "has taken on nationwide, worldwide implications," Tyler said.

California's top court led the nation in 1948 when it was the first state high court to legalize interracial marriage. In 1979, the court upheld gay rights by saying business could not arbitrarily discriminate against gays.

San Francisco City Attorney Dennis Herrera, who is mayor Newsom's attorney in the mayor's litigation, said his opponents' petition to the Supreme Court was "wholly unconvincing."

He said the issue should percolate in the lower courts so that the Supreme Court could decide the question "with the aid of lower court findings."

One of the last times the high court took a case without lower court action was in 1999, when the justices stripped from the voter ballot an initiative that would have reduced legislators' pay while reassigning reapportionment power from the Legislature to the Supreme Court.

Just last week, the justices declined to hear a challenge to Schwarzenegger's move reducing vehicle registration fees. Opponents of the tax decrease, fearing immediate budget cuts, urged the court to act without any lower court action.

But perhaps the most publicized cases in which the justices declined to hear a challenge came last year, weeks before California's gubernatorial recall election. Despite claims of electoral fraud in the gathering of signatures of registered voters that forced the recall, the Supreme Court sent the case down to the lower courts, where it was left unresolved before Schwarzenegger ousted Gov. Gray Davis from office in October.

The case is Lewis v. Alfaro, S122865.