By Jeff Labrecque
Updated June 14, 2011 at 07:52 PM EDT

Hugh Hefner is officially back on the market. His 25-year-old fiancée, Crystal Harris, who he was planning to marry this Saturday, has broken their engagement. “The wedding is off,” the 85-year-old Playboy founder tweeted today. “Crystal has had a change of heart.”

It would’ve been the third marriage for Hefner. Harris, who reportedly has moved out of the Playboy mansion, according to TMZ, was the magazine’s Playmate of the Month in December 2009.