The California Supreme Court (search) declined a request by the state attorney general Friday to immediately shut down San Francisco's gay weddings and nullify the nearly 3,500 marriages already performed.

The decision marked yet another setback to conservatives in their fight to block the rush to the altar by gay couples in San Francisco. More than 3,400 couples have tied the knot since the city began issuing marriage licenses two weeks ago, under the directive of Mayor Gavin Newsom.

At the prodding of Gov. Arnold Schwarzenegger (search), Attorney General Bill Lockyer (search) asked the justices to intervene in the emotionally charged debate while they consider the legality of the marriages. But the justices declined, and told the city and a conservative group that opposes gay marriages to file new legal briefs by March 5.

Without taking a position on whether same-sex marriages should be deemed constitutional, Lockyer told the justices it was a matter for the courts — not the mayor — to decide.

"The genius of our legal system is in the orderly way our laws can be changed, by the Legislature or by a vote of the people through the initiative process, to reflect current wisdom or societal values," he wrote.

Regardless of the Friday order, the San Francisco-based court did not indicate whether it would decide the issue. The seven justices usually are reluctant to decide cases until they work their way up through the lower courts, which this case has not.

"It's a matter of statewide concern and voters want to know, Californians want to know and couples that participated in ceremonies need to know the status of their relationship," Lockyer said.

The court challenge came as 25 gay couples exchanged wedding vows Friday on the steps of village hall in New Paltz, N.Y., opening up another front in the growing national debate.

A county clerk in New Mexico issued 26 licenses earlier this month before the state attorney general declared them invalid. More than 30 gay couples in Iowa City, Iowa, were denied marriage licenses Friday by an openly lesbian county official who said she must uphold the law.

"What we're witnessing in America today is the flowering of the largest civil rights movement the country's had in a generation," said New Paltz' Green Party mayor, Jason West.

New York Attorney General Eliot Spitzer (search) refused a request for an injunction against the New Paltz ceremonies, noting that such a measure should only be a last resort. He did not issue an opinion on whether the marriages were legal.

"The validity of the marriages and the legality of the mayor's action will be determined in due course in the courts," Spitzer said.

This month's gay marriage push is rooted in a November decision by the Massachusetts Supreme Judicial Court, which ruled that prohibiting same-sex marriages violated that state's constitution. The court reaffirmed the decision this month, clearing the way for full-fledged gay marriages by mid-May.

The issue has sparked intense debate nationwide and spilled into the presidential race. President Bush, citing the Massachusetts decision and the parade of weddings in San Francisco, backed a federal constitutional amendment Tuesday to bar such marriages. "A few judges and local authorities are presuming to change the most fundamental institution of civilization," Bush said.

In statehouses nationwide, lawmakers are taking a closer look at their constitutions to see if they could be construed to permit same-sex marriages, even in states where laws now bar them. Massachusetts is one of many states where lawmakers are considering a constitutional amendment to bar the marriages.

The San Francisco mayor sued the state last week on grounds that California's marriage laws violate the state constitution's equal-protection clause. Pressure on Lockyer to act intensified when Schwarzenegger directed him to "take immediate steps" to halt San Francisco's marriage march.

Supporters of the marriages have criticized Lockyer for rushing the issue to the state's highest court, while gay marriage opponents have criticized Lockyer for not acting sooner.

The California Supreme Court has a history of addressing marriage and gay rights cases. It was the first state high court in the nation to legalize interracial marriage 56 years ago. Twenty-five years ago, the court upheld gay rights by saying businesses could not arbitrarily discriminate against homosexuals.

Meanwhile, Republican activists who helped mount the recall of former Gov. Gray Davis last year have announced plans to seek the removal of Lockyer, who they say has "neglected his duty" to enforce state marriage laws.

In another development related to the weddings, the Social Security Administration has told its offices nationwide not to accept marriage certificates from San Francisco as proof of identification for newlyweds looking to make name changes on Social Security cards.