Gay and lesbian couples in California could regain the right to marry as early as next month if the Supreme Court decides not to hear a case on the state's gay marriage ban, Proposition 8.

In 2008, voters narrowly approved the amendment to the state's constitution in response to a California Supreme Court ruling which legalized such unions.

Approximately 18,000 couples married before Proposition 8 was approved.

The amendment was found to be unconstitutional by a federal district court in 2010 and the ruling was upheld by the Ninth Circuit Court of Appeals.

Prop 8 supporters earlier this year asked the Supreme Court to review the decision.

According to the American Foundation for Equal Rights (AFER), the group formed specifically to challenge the ban, the high court's decision to take the case could come as early as September 25.

If the court agrees to hear the case, oral arguments would be presented in the spring, and a final decision would likely be issued by June 2013, AFER said.

A decision not to hear the case is expected as early as October 1. In that case, the Ninth Circuit decision which ruled the ban unconstitutional would be made permanent. AFER said that it expects marriages would resume within several days after the Supreme Court denies review.