The outspoken Oscar-winner met with Argentinian President Cristina Kirchner in Buenos Aires to offer his support in the sovereignty dispute.
Using the South Atlantic islands' Spanish name, he urged British officials to enter into negotiations with Argentina as the 30th anniversary of the Falklands War approaches.
He says, "I know I came at a very sensitive moment in terms of diplomacy between Argentina and the U.K. over the Malvinas.
"I hope that diplomats can establish true dialogue in order to solve the conflict.
"The world today cannot tolerate ridiculous demonstrations of colonialism. The way of dialogue is the only way to achieve a better solution for both nations...
"It's necessary that these diplomatic talks happen between the United Kingdom and Argentina. I think that the world today is not going to tolerate any kind of ludicrous and archaic commitment to colonialist ideology."
Both countries' governments claim responsibility for the Falkland Islands.