Director Ben Affleck wins the feature film award at the 65th annual Directors Guild Of America Awards.

Director Ben Affleck wins the feature film award at the 65th annual Directors Guild Of America Awards. Photo: AFP

Ben Affleck has won the top film honour from the Directors Guild of America for his CIA thriller Argo, further sealing its status as best picture frontrunner at the Academy Awards.

Saturday's prize also normally would make Affleck a near shoo-in to win best director at the February 24 Oscars, since the Directors Guild recipient nearly always goes on to claim the same prize at Hollywood's biggest night.

But Affleck surprisingly missed out on an Oscar directing nomination, along with several other key favourites, including fellow Directors Guild contenders Kathryn Bigelow for Zero Dark Thirty and Tom Hooper for Les Miserables.

Affleck's Oscar snub has not hurt Argo and may even have earned it some favour among awards voters as an underdog.

Argo has dominated other awards since the Oscar nominations.

"I don't think that this makes me a real director, but I think it means I'm on my way," said Affleck, who won for just his third film behind the camera.

Backstage at the Directors Guild honours, Affleck said he had nothing but respect for the academy and that "you're not entitled to anything".

With 12 Oscar nominations, Steven Spielberg's Civil War saga Lincoln initially looked like the favourite over Argo, Les Miserables and Zero Dark Thirty, since films generally have little chance of winning best picture if they are not nominated for best director.

Only three films have done it in 84 years, most recently 1989's best picture Driving Miss Daisy, which failed to earn a directing nomination for Bruce Beresford.

But Affleck's Argo, in which he also stars as a CIA operative who hatches a bold plan to rescue six Americans during the hostage crisis in Iran, has swept up all the major awards since the Oscar nominations.

Argo won best drama and director at the Golden Globes and top film honours from the Screen Actors Guild and the Producers Guild of America.

Peer loyalty might play in Affleck's favour at the Oscars. The acting branch in particular, the largest block of the academy's 5900 members, might throw its weight behind Argo because of Affleck's directing snub.

Actors love it when one of their own moves into a successful directing career, and Affleck - who's rarely earned raves for his dramatic chops - also delivers one of his best performances in Argo.

AP