A federal appeals court has ruled that Virginia's same-sex marriage ban is unconstitutional, the latest in a string of decisions overturning bans across the country.

And Monday's ruling by three-judge panel of the 4th U.S. Circuit Court of Appeals in Richmond could reverberate soon in South Carolina, which is one of 31 states that prohibit such marriages and which is covered by the same circuit.

Just hours after the ruling, North Carolina Attorney General Roy Cooper said his prosecutors will drop their opposition to challenges to that state's same-sex marriage ban. He said it's time for attorneys representing the state to "stop making arguments we will lose."

S.C. Attorney General Alan Wilson sees no need to change course because the U.S. Supreme Court will likely make the final decision about gay marriage, Wilson's spokesman Mark Powell said.

South Carolina's gay marriage ban remains intact, but Victoria Middleton, executive director of South Carolina's chapter of the American Civil Liberties Union, said Monday's decision "should give hope to all same-sex couples in South Carolina who seek the freedom to marry, and to everyone who supports the right to make that commitment."

The Fourth Circuit panel ruled that Virginia's constitutional and statutory provisions barring gay marriage and denying recognition of such unions performed in other states violate the U.S. Constitution. The Virginia gay marriage case is one of several that could go to the U.S. Supreme Court.

It was not immediately clear if or when the state would need to begin issuing marriage licenses to same-sex couples.

Virginia's same-sex marriage bans "impermissibly infringe on its citizens' fundamental right to marry," Judge Henry F. Floyd wrote in the court's opinion.

In South Carolina, the battle for marriage equality is scheduled to take another twist Wednesday morning in a Greenville courtroom.

That's when six local gay couples will apply for marriage license at the Greenville County Probate Court in order to call for the freedom to marry, said Aaron Sarver, spokesman for the Campaign for Southern Equality.

They will be joined by family, friends and clergy, who will lead a prayer service. Piedmont residents Ivy Hill and Misha Gibson are engaged to be married but have twice been denied a marriage license in South Carolina.

"Each time we have been denied, but we will continue to walk up to that counter and call for full equality on a federal level for all LGBT people until they say yes," Hill said in a statement. "We apply because we believe that everyone's hearts and minds can change around these issues once they see how human we actually are."

South Carolina has about 7,200 same-sex couples, according to 2010 US Census data. In recent months, federal courts in Utah, Oklahoma, Tennessee, Ohio, Texas and Kentucky also have found bans on same-sex marriage to be unconstitutional, Sarver noted.

He also noted a 2013 poll found 39 percent of South Carolina residents support marriage equality, up from previous years.

Middleton said same-sex couples deserve the same legal protections as other couples. "No one should have to feel as though their family occupies second-class status," she said.

In February, U.S. District Judge Arenda Wright Allen ruled that Virginia's same-sex marriage ban violates the U.S. Constitution's equal protection and due process guarantees. Lawyers for two circuit court clerks whose duties include issuing marriage licenses appealed. Attorney General Mark Herring, representing a state official also named as a defendant, sided with the plaintiffs.

"Marriage is one of the most fundamental rights - if not the most fundamental right - of all Americans," David Boies, an attorney for the plaintiffs, said in a statement. "This court has affirmed that our plaintiffs - and all gay and lesbian Virginians - no longer have to live as second-class citizens who are harmed and demeaned every day."

Gay marriage proponents have won more than 20 legal decisions around the country since the U.S. Supreme Court last year struck down a key part of the federal Defense of Marriage Act. Those rulings remain in various stages of appeal.

The Virginia lawsuit was filed by Timothy Bostic and Tony London of Norfolk, who were denied a marriage license, and Carol Schall and Mary Townley of Chesterfield County. The women were married in California and wanted their marriage recognized in Virginia, where they are raising a 16-year-old daughter.

In 2006, Virginians voted 57 percent to 43 percent to approve the constitutional amendment banning gay marriage. Virginia laws also prohibit recognition of same-sex marriages performed in other states.

That same year, South Carolinians voted more than 3-1 to approve a similar amendment, and it also doesn't recognize same-sex marriages in other states.