Supreme Court Chief Justice John G. Roberts Jr. on Friday called for a response by Monday to a clerk's request to stay an appeals court's ruling striking down Virginia's ban on gay marriage.

Michelle B. McQuigg, clerk of Prince William County's Circuit Court, turned to the Supreme Court after a 3-judge panel of the Fourth Circuit Court of Appeals in Richmond denied her request to stay its ruling.

(Related: Federal appeals court denies stay in Virginia gay marriage case.)

Without the Supreme Court's intervention, gay and lesbian couples could start marrying as early as Thursday. The decision would also affect similar bans in West Virginia, North Carolina and South Carolina.

The high court set a Monday, August 18 deadline for plaintiffs to respond to McQuigg's request.

McQuigg is represented by the Christian conservative Alliance Defending Freedom