PARIS — Monaco’s Prince Albert II is filing a lawsuit in the U.S. against an American who claims he once worked as the prince’s personal spymaster and is owed back pay, the prince’s French lawyer said Friday.

Claims by Robert Eringer appearing in the media "smear" the image of the ruling prince and the reputation of Monaco, a tiny Riviera principality, the royal palace said. The claims are "for the most part baseless," a statement said.