SAN FRANCISCO — The California Supreme Court yesterday rejected petitions to delay its historic same-sex marriage decision, clearing the way for gay couples to marry later this month.

The court’s action on the case — which makes it possible for same-sex unions to begin June 17 — was unusually quick. Most appeals, even unsuccessful ones, trigger a 30- to 60-day delay in the effective date of a ruling. Acting in closed session, the court voted 4-3 to reject petitions by Christian groups that it reconsider its May 15 ruling. The court also refused to delay the effective date of the decision until after the November election, when voters will consider a constitutional amendment to reinstate the ban on same-sex marriage.

The court’s action means the marriage ruling becomes effective at 5 p.m. on June 16. Counties and cities are expected to issue marriage licenses to same-sex couples the following day.

Christian groups backing the November measure to reinstate the marriage ban warned that gays who marry before then may have their marriages nullified if voters approve the measure. Legal analysts, however, think the marriages would remain intact even if voters decide to limit marriage to opposite-sex couples.

The founder of Liberty Counsel, Mathew Staver, said the court’s decision “reveals the political agenda of a handful of judges.”

“Judges acting as judges and not as legislators would have granted the stay,” Mr. Staver said. “The battle over marriage is far from over and will not be decided by four judges. The people will decide in November.”