A U.S. federal judge who had overturned California's same-sex marriage ban decided on Thursday to lift the stay of the ruling, meaning same-sex marriage may soon resume in the state.

Chief U.S. District Judge Vaughn Walker of San Francisco said in an order that the lift of the stay will be effective from Aug. 18.

Walker last week struck down Proposition 8, a California constitutional amendment approved by voters in November 2008 that banned same-sex marriage.

Walker at that time issued a temporary stay that froze the enforcement of the ruling.

Proponents of Proposition 8 had asked for the stay, saying allowing same-sex couples to marry pending the appeal would create confusion if Walker's ruling was eventually overturned.

Lawyers for same-sex couples, California Governor Arnold Schwarzenegger and Attorney General Jerry Brown opposed the stay and had filed legal motions calling for resumption of same-sex marriages.

"None of the factors the court weighs in considering a motion to stay favors granting a stay. Accordingly, proponents' motion for a stay is denied," Walker said in the latest order.

"Because proponents fail to satisfy any of the factors necessary to warrant a stay, the court denies a stay except for a limited time solely in order to permit the court of appeals to consider the issue in an orderly manner," Walker said.

Thursday's order still gives time for Proposition 8 supporters to appeal for another stay. It is a new twist in the high-profile case that many believe will go to the U.S. Supreme Court.