Actress Ashley Olsen is planning to marry National Treasure star Justin Bartha in a secret $1 million ceremony on the French Riviera, according to reports. The pair is rumoured to be in discussions about possible nuptials in the South of France next summer.

According to the National Enquirer, 22-year-old Olsen's wedding party will include twin sister Mary-Kate, her 19-year-old sister Lizzie and half-sister Taylor, 12. Her two brothers are said to have been enlisted as groomsmen for the event.

A source tells the tabloid, "Ashley has dreamed of having her wedding on the French Riviera, and she's going to ask her favourite designer, Karl Lagerfeld, to create a custom-designed gown... She also wants photographer Annie Leibovitz, who Mary-Kate has worked with, to capture the entire extravaganza on film."