VENICE, Italy — Oscar-winning director Bernardo Bertolucci initially didn't want to head the Venice Film Festival's jury, saying it's "tremendously tiring."

But the 73-year-old Italian said he "caved in" after festival director Alberto Barbera wrote a letter in which "he succeeded to present some responsibilities I would have for cinema, above all for those who are starting out."

"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.

Loading Slideshow...
  • ITALY-CINEMA-VENICE-FILM-FESTIVAL

    US director Gia Coppola poses during the photocall of 'Palo Alto' presented in the Orizzonti selection at the 70th Venice Film Festival on September 1st, 2013 at Venice Lido. AFP PHOTO / TIZIANA FABI (Photo credit should read TIZIANA FABI/AFP/Getty Images)

  • Gia Coppola

    Director Gia Coppola poses for photographers during the photo call for the film Palo Alto at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/David Azia)

  • Maserati On The Red Carpet Of The 70th Venice International Film Festival - September 1, 2013

    VENICE, ITALY - SEPTEMBER 01: Actor James Franco attends 'Palo Alto' Premiere during the 70th Venice International Film Festival at Sala Grande on September 1, 2013 in Venice, Italy. (Photo by Vittorio Zunino Celotto/Getty Images for Maserati)

  • 'Palo Alto' Premiere - The 70th Venice International Film Festival

    VENICE, ITALY - SEPTEMBER 01: Actor James Franco attends the 'Palo Alto' Premiere during the 70th Venice International Film Festival at the Sala Grande on September 1, 2013 in Venice, Italy. (Photo by Pascal Le Segretain/Getty Images)

  • 'Palo Alto' Premiere - The 70th Venice International Film Festival

    VENICE, ITALY - SEPTEMBER 01: Director Gia Coppola, actors James Franco and Claudia Levy attend the 'Palo Alto' Premiere during the 70th Venice International Film Festival at the Sala Grande on September 1, 2013 in Venice, Italy. (Photo by Pascal Le Segretain/Getty Images)

  • ITALY-CINEMA-VENICE-FILM-FESTIVAL

    from left : Jacqui Getty, US director Gia Coppola, actress Claudia Levy and US actor James Franco pose during the photocall of 'Palo Alto' presented in the Orizzonti selection at the 70th Venice Film Festival on September 1st, 2013 at Venice Lido. AFP PHOTO / TIZIANA FABI (Photo credit should read TIZIANA FABI/AFP/Getty Images)

  • ITALY-CINEMA-VENICE-FILM-FESTIVAL

    US actor and director James Franco poses during the photocall of 'Palo Alto' presented in the Orizzonti selection at the 70th Venice Film Festival on September 1st, 2013 at Venice Lido. AFP PHOTO / TIZIANA FABI (Photo credit should read TIZIANA FABI/AFP/Getty Images)

  • ITALY-CINEMA-VENICE-FILM-FESTIVAL

    US actor and director James Franco poses during the photocall of 'Palo Alto' presented in the Orizzonti selection at the 70th Venice Film Festival on September 1st, 2013 at Venice Lido. AFP PHOTO / TIZIANA FABI (Photo credit should read TIZIANA FABI/AFP/Getty Images)

  • James Franco

    Actor James Franco poses for photographers as she arrives on the red carpet for the film Palo Alto at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/Andrew Medichini)

  • Claudia Levy, James Franco

    Actors Claudia Levy and James Franco pose for photographers during the photo call for the film Palo Alto at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/David Azia)

  • James Franco

    Actor James Franco poses for photographers as she arrives on the red carpet for the film Palo Alto at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/Andrew Medichini)

  • James Franco, Gia Coppola

    Director Gia Coppola and actor James Franco poses for photographers as she arrives on the red carpet for the film Palo Alto at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/Andrew Medichini)

  • James Franco

    Actor James Franco signs autographs as he arrives on the red carpet for the film Palo Alto at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/Andrew Medichini)

  • Celebrities At The Terrazza Maserati - Day 5 - The 70th Venice International Film Festival

    VENICE, ITALY - SEPTEMBER 01: Actor Daniel Radcliffe attends the 70th Venice International Film Festival at Terrazza Maserati on August 31, 2013 in Venice, Italy. (Photo by Tullio M. Puglia/Getty Images for Maserati)

  • 'Kill Your Darlings' Premiere - The 70th Venice International Film Festival

    VENICE, ITALY - SEPTEMBER 01: Daniel Radcliffe attends 'Kill Your Darlings' Premiere during the 70th Venice International Film Festival at Palazzo Del Cinema on September 1, 2013 in Venice, Italy. (Photo by Pascal Le Segretain/Getty Images)

  • Alternative View At The 70th Venice International Film Festival

    VENICE, ITALY - SEPTEMBER 01: (EDITORS NOTE: This image was processed using digital filters) Actor Daniel Radcliffe attends 'Kill Your Darlings' Premiere during the 70th Venice International Film Festival at Palazzo Del Cinema on september 1, 2013 in Venice, Italy. (Photo by Gareth Cattermole/Getty Images)

  • 'Kill Your Darlings' Premiere - The 70th Venice International Film Festival

    VENICE, ITALY - SEPTEMBER 01: Daniel Radcliffe attends 'Kill Your Darlings' Premiere during the 70th Venice International Film Festival at Palazzo Del Cinema on September 1, 2013 in Venice, Italy. (Photo by Pascal Le Segretain/Getty Images)

  • Daniel Radcliffe and director John Krokidas

    Actor Daniel Radcliffe arrives at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/Andrew Medichini)

  • Daniel Radcliffe and director John Krokidas

    Actor Daniel Radcliffe and director John Krokidas arrive at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/Andrew Medichini)

  • Daniel Radcliffe, John Krokidas

    Actor Daniel Radcliffe, right, and director John Krokidas arrive for the screening of Kill Your Darlings at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/David Azia)

  • Daniel Radcliffe

    Actor Daniel Radcliffe poses for photographers as he arrives for the screening of Kill Your Darlings at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/David Azia)

  • Daniel Radcliffe

    Actor Daniel Radcliffe turns back as he arrives for the screening of Kill Your Darlings at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/David Azia)

  • Daniel Radcliffe, John Krokidas

    Actor Daniel Radcliffe, right, and director John Krokidas arrive for the screening of Kill Your Darlings at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/David Azia)

  • Daniel Radcliffe

    Actor Daniel Radcliffe poses for photographers as he arrives for the screening of Kill Your Darlings at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/David Azia)

  • Daniel Radcliffe

    Actor Daniel Radcliffe poses for photographers as he arrives for the screening of Kill Your Darlings at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/Andrew Medichini)

  • Daniel Radcliffe

    Actor Daniel Radcliffe poses for photographers as he arrives for the screening of Kill Your Darlings at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Sunday, Sept. 1, 2013. (AP Photo/Andrew Medichini)

  • 'The Zero Theorem' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - SEPTEMBER 02: Director Terry Gilliam attends 'The Zero Theorem' Photocall during the 70th Venice International Film Festival at the Palazzo del Casino on September 2, 2013 in Venice, Italy. (Photo by Pascal Le Segretain/Getty Images)

  • Gia Coppola

    Director Gia Coppola poses for portraits at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Monday, Sept. 2, 2013. (AP Photo/Domenico Stinellis)

  • Alfonso Cuaron, Sandra Bullock, George Clooney

    Director Alfonso Cuaron, actors Sandra Bullock and George Clooney pose for photographers the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Wednesday, Aug. 28, 2013. (AP Photo/Andrew Medichini)

  • Sandra Bullock, George Clooney

    Actors Sandra Bullock and George Clooney arrive to promote their film Gravity at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Wednesday, Aug. 28, 2013. (AP Photo/David Azia)

  • Sandra Bullock, George Clooney

    Actors Sandra Bullock and George Clooney arrive to promote their film Gravity at the 70th edition of the Venice Film Festival held from Aug. 28 through Sept. 7, in Venice, Italy, Wednesday, Aug. 28, 2013. (AP Photo/David Azia)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actress Sandra Bullock arrives at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors George Clooney and Sandra Bullock meet fans at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actress Sandra Bullock arrives at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actress Sandra Bullock meet fans at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Pascal Le Segretain/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors George Clooney and Sandra Bullock meet fans at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors George Clooney and Sandra Bullock meet fans at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney attend the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Ian Gavan/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors George Clooney and Sandra Bullock arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors Sandra Bullock and George Clooney arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)

  • 'Gravity' Photocall - The 70th Venice International Film Festival

    VENICE, ITALY - AUGUST 28: Actors George Clooney and Sandra Bullock arrive at the 'Gravity' photocall during the 70th Venice International Film Festival at the Palazzo del Casino on August 28, 2013 in Venice, Italy. (Photo by Andreas Rentz/Getty Images)