The justices declined without comment to intervene and block clerks from issuing marriage licenses to gay couples in Massachusetts. That state's highest court had ruled in November that the state Constitution allows gay couples to marry, and declared that the process would begin on Monday.
The Supreme Court's decision, in an emergency appeal filed Friday by gay marriage opponents, does not address the merits of the claim that the state Supreme Judicial Court overstepped its bounds with the landmark decision.
A stay had been sought by a coalition of state lawmakers and conservative activists.
A staunch opponent of same-sex marriage, Republican Governor Mitt Romney pointed to an old state law limiting licenses to state residents only, reports CBS News Correspondent Mika Brzezinski. "We have to follow the law whether it's one we appreciate or not," he said of the court's decision to allow gay marriage.
But officials in other parts of the state say they will issue licenses to out-of state-couples in spite of Governor Romney's objections, reports Brzezinski.
A federal judge ruled against them on Thursday, and the Boston-based 1st U.S. Circuit Court of Appeals upheld that decision on Friday, setting up the Supreme Court appeal. The appeals court agreed to hear arguments on the request to bar same-sex unions in June, after several weeks of legal gay marriages.
The stay request had been filed with Supreme Court Justice David Souter, a Massachusetts native who handles appeals from the region. He referred the matter to the full nine-member court.
Mathew Staver, president and general counsel of the Florida-based Liberty Counsel, had told justices in a filing that they were not asking the Supreme Court "to take any position on the highly politicized and personally charged issue of same-sex marriage."
Instead, Staver wrote, they wanted the court to consider whether the Massachusetts judges wrongly redefined marriage. That task should be handled by elected legislators, he said.
In the Supreme Court's last ruling involving gay rights, justices ruled last year that states may not punish gay couples for having sex. In a dissent, Justice Antonin Scalia complained that the court "has largely signed on to the so-called homosexual agenda" and was inviting same-sex marriage.
CBS News Legal Analyst Andrew Cohen reports "the issues aren't going to go away even if Massachusetts begins to issue same-sex marriage licenses.
"And how those licenses are issued, and what effect they have in Masschusetts, will have an effect on the legal case as it goes forward."