Updated

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

The lawsuit was filed by the Alliance Defense Fund (search) less than a week after two state judges declined to stop San Francisco city officials from issuing the marriage licenses, more than 3,200 of which have been granted since Feb. 12.

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

State law bars gay marriage. But Mayor Gavin Newsom has argued that the California Constitution's equal protection clause trumps state law and requires that all persons be treated equally.

California Attorney General Bill Lockyer plans to ask the state Supreme Court on Friday to decide whether San Francisco authorities are violating the law.

But conservative groups have said they do not trust Lockyer, a leading Democrat and potential rival to Gov. Arnold Schwarzenegger in the 2006 election, to defend their position vigorously.

Lockyer said he was unfazed by the criticism, which he described as "just part of my job."

In 1948, California's high court was the first in the nation to legalize interracial marriage. In 1979, the court boosted gay rights by saying businesses could not arbitrarily discriminate against gays.

Jon Davidson, an attorney for the gay rights group Lambda Legal Defense and Education Fund, said the latest appeal "is about politics, not the law."

San Francisco City Attorney Dennis Herrera, who represents the mayor in the litigation, said his opponents' petition to the Supreme Court was "wholly unconvincing." He said the issue should be weighed by lower courts so the Supreme Court can decide the question "with the aid of lower court findings."

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