Iranian film Nader and Simin, A Separation won top honours at the Berlin Film Festival. ((Asghar Farhadi))

Iranian director Asghar Farhadi's Nader and Simin, A Separation, a drama that centres on a disintegrating marriage, won the top Golden Bear honour and swept the acting awards at the Berlin film festival on Saturday.

A jury led by actress Isabella Rossellini handed the ensemble cast of the film, led by Peyman Moadi and Leila Hatami, both the best actor and the best actress awards.

"I never would have thought that I would win this prize," Farhadi said. He added that it offers "a very good opportunity to think of the people of my country — the country I grew up in, the country where I learned my stories — a great people."

Farhadi was honoured as best director in Berlin two years ago for his previous movie, About Elly.