Uma Thurman and hotelier Andre Balazs have ended their three-year, on-again off-again relationship, a source close to the actress tells PEOPLE.
The breakup of Thurman, 36, and Balazs, 50 – who had begun dating in late 2003 – takes place amid rumors that the couple were planning to wed in the Caribbean this summer.
Thurman's publicist, Robert Garlock, did not wish to comment on Sunday.
Just over a year ago at this time, after Thurman appeared at the 2006 Oscars without Balazs, Garlock issued a statement saying that the Kill Bill actress and Balazs – who owns such properties as New York's Mercer Hotel and the Chateau Marmont and the Standard in Los Angeles – had ended their relationship.
"Unfortunately, it is true," said the March 8, 2006, statement. "But we remain close friends."
By last fall, however, the two were again more than just friends, being seen together everywhere from Copenhagen to New York – which Thurman and her two children by former husband Ethan Hawke call home.
Thurman and Hawke were together for six years, until she filed for divorce in 2003.
Thurman is currently filming The Accidental Husband, in which she stars as a talk-radio host who gets into trouble after dishing out love advice.