"Probably after the festival I will return to Rome and I will burn that letter," Bertolucci said Wednesday on the film fest's opening day.
The 70th edition kicked off Wednesday with Sandra Bullock and George Clooney starring in the 3D space odyssey "Gravity," which made its world premiere out of competition.
Contenders for the coveted Golden Lion include Terry Gilliam's "The Zero Theorem," Peter Landesman's "Parkland" and Kelly Reichardt's "Night Moves." Prizes will be announced Sept. 7.
"I have to say what I want most is to be surprised also in the prizes we award," Bertolucci said.
The 12-day festival requires the main jury to screen 20 films for the Golden Lion.
But Bertolucci, who won an Oscar in 1987 for directing "The Last Emperor," said Barbera's letter promised Bertolucci 18 films in competition for the Golden Lion, but made it 20 when the lineup was officially announced, to Bertolucci's chagrin.
"He told me it was not correct," Barbera conceded.
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