SAN FRANCISCO - A California judge on Tuesday gave the city of San Francisco a green light to keep on issuing marriage licenses to gays and lesbians until late March at least.

Conservative family groups had asked two courts to halt the flood of City Hall weddings that have made San Francisco "Ground Zero" for the controversial gay marriage movement.

One court put off its hearing in the case until Friday but the judge in the second case, California Superior Court Judge James Warren, refused to issue a temporary restraining order to stop the practice started last Thursday by the city's new mayor and gay rights advocate, Gavin Newsom.

"There will not be a stay ... The requirements have not been met to issue an injunction," Judge Warren said as he scheduled his next hearing for March 29.

Warren said no immediate threat to society existed that warranted putting a stop to the issuance of same-sex marriage licences.

However, the judge in a second lawsuit filed by the Campaign for California Families (CCF) could decide on Friday to halt the issuance of marriage licenses to same-sex couples.

Some legal analysts thought that the judge in the CCF case may follow Warren's lead and also deny a halt to same-sex marriages because the two lawsuits are similar.

The city's assessor-record's office said that about 2,500 gay and lesbian couples have been married since Newsom ordered city officials to defy a state law mandated by voters and grant same-sex marriage licenses.

Newsom decided to lift the ban on the grounds that homosexuals have the right to wed under the state's equal protection clause.

But the move defied Proposition 22, approved in 2000 by California voters, that restricted marriage only to heterosexual couples. The measure passed with support from about 60 per cent of those who voted on the initiative.

Robert Tyler, lead attorney for the Alliance Defense Fund (ADF), says San Francisco violated state law and created "municipal anarchy" by granting same-sex marriage licenses.

In court on Tuesday, Tyler said third parties, such as insurance companies and private employers, also needed to know the legal status of same-sex marriage licenses.

"These parties are going to ask: will we need to give these couples the same benefits as married heterosexual couples? If not, they could be sued and that could clog up the courts," he said.

(Agencies via Xinhua)