The prince, 52, is the son of the late Prince Rainier III, Louis Henri Maxence Bertrand Grimaldi, and the late Princess Grace, a one-time Hollywood screen icon.
Prince Albert II succeeded his father, Prince Rainier III, July 12, 2005.
The palace did not say whether Prince Albert II and Wittstock, a former Olympic swimmer, had set a wedding date. No other details regarding the royal proposal were released.
Celebrity Families of 2014 [PHOTOS]