California's Supreme Court has decided to hear three legal challenges to a gay-marriage ban approved by the state's voters earlier this month, the court said Wednesday.

The state's top court is refusing, however, to allow gay couples to resume marrying until it rules. The court did not elaborate on its decision.

The amendment, known as Proposition 8, was the subject of a heated, costly battle ahead of election day and passed with 52 per cent of the vote. If it holds, the proposition will overrule a California Supreme Court decision last May that made marriage between two members of the same sex legal.

Gay-rights legal groups filed a petition following the Nov. 4 vote, asking the Supreme Court to invalidate Proposition 8 on the grounds that voters did not have the authority to make such a dramatic change in state law without approval from the legislature.

The three cases slated for review by the Supreme Court also argue the amendment infringes on the civil rights of a vulnerable minority group.

The state's top court refused to hear a similar petition in June, when gay-rights activists tried to knock the measure off the ballot.

The measure's sponsors, known as the Yes on 8 campaign, as well as Attorney General Jerry Brown, have implored the court's seven justices to examine whether the amendment can stand as is.

Both groups have been instructed by the court that they have until Dec. 19 to submit arguments as to why the amendment shouldn't be nullified. Lawyers for the plaintiffs, who include gay couples that weren't married before the vote, must respond before Jan. 5.

Oral arguments could begin by March, according to court spokeswoman Lynn Holton.

Thirty states in the U.S. have banned gay marriage, although several permit civil unions or domestic partnerships that recognize some marriage rights.

The only two states that allow same-sex marriage are Massachusetts and Connecticut.

With files from the Associated Press