The US Supreme Court has said it will not hear a case that challenges the legality of same-sex marriages.
Gay marriage has become an important political issue in the US
The judges had been asked to overturn a decision by a Massachusetts court that legalised gay weddings and had been challenged by conservative groups.
The issue has become an important one politically and is widely seen to have helped President Bush win re-election.
Mr Bush vowed to push for an amendment to the constitution in his second term that would prohibit same-sex marriage.
However, there does not appear to be enough support for this in congress, which means it will either remain an issue for individual states to resolve, or it will come back to the Supreme Court in another form on another day, says the BBC's Ian Pannell in Washington.
Voters in 11 states approved constitutional amendments banning gay
marriage in November elections.
The Supreme Court judges did not comment on why they declined to rule on the case, but their refusal is a setback for opponents of same-sex marriage.
"This was a weak and misguided legal effort from right-wing
anti-gay groups that never really stood much chance of being heard at
the Supreme Court," said David Buckel of the Washington-based Lambda
Legal organisation, a gay rights advocacy group.
Massachusetts has been the only US state since last year to allow gay marriage, prompting thousands of gay couples to flock to courthouses around the state in May.
But opponents challenged the decision, saying the Massachusetts high court had overstepped its authority by trying to rewrite laws that are the preserve of Congress.