After a three-year marriage that gave birth to the AFI Dallas Film Festival, the Dallas Film Society and the American Film Institute have announced an amicable separation.

AFI and the film society said in a joint statement Monday that they had completed their initial three-year agreement, adding that they were discussing ways of working together in the future.

Ruth O’Donnell Mutch, the festival’s first donor and chair of the board of directors, said of AFI: “This relationship has helped Dallas to take its place among the nation’s top 20 film festivals, with more than 100,000 attendees in our first three years.”

The film society also said it was planning its 2010 festival and expects to announce details over the coming weeks. Artistic director Michael Cain said that the event would be held during the usual period including the last week in March and first week in April.

This year’s event drew about 40,000 and included screenings of “The Brothers Bloom,” “The Hurt Locker,” “The Cove,” “The Burning Plain” and “Tyson.”