WASHINGTON (AP) - The Supreme Court has refused to hear an appeal challenging President Barack Obama's U.S. citizenship and his eligibility to serve as commander in chief.

Without comment, the high court on Monday refused to hear an appeal from Alan Keyes, Wiley Drake and Markham Robinson.

The 9th U.S. Circuit Court of Appeals ruled the challengers did not have legal standing to file the lawsuit.

The U.S. Constitution says only "a natural born citizen" may serve as president.

The challengers allege that Obama, whose father was Kenyan, was born in that African country, rather than in Hawaii.

They claim his Hawaii birth certificate is a forgery.

Hawaii officials have repeatedly verified Obama's citizenship.

Keyes and Drake ran against Obama on the American Independent Party ticket and Robinson serves as the party's chairman.