The film, based on the real-life story of a Brooklyn lawyer caught up in the politics of the Cold War between Russia and the U.S., was pitched to studio bosses at MGM in 1965, but they felt the time wasn't right for such a hard-hitting film.

Hanks explains he didn't even know about his character James Donovan's story two years ago - and he only learned about the link to Peck and Guinness when he started speaking to the attorney's family.

"I was fuelled with no pre-conceived knowledge of James Donovan," Hanks tells WENN. "I knew nothing about this story two years ago. That all came to me, as all good stories come to us, in a surprise package, because it was simply a piece of history that was so compelling personally for me.

"I was meeting with the Donovan family - two daughters and the son - and I found out something I never knew before. In 1965 Gregory Peck came after the story and he got Alec Guinness to agree to play Rudolf Abel (a Soviet intelligence officer arrested on charges of conspiracy by FBI agents in 1957).

"Peck was gonna play Donovan and then MGM at the time said, 'No, I don't think we're gonna tell the story!' And I didn't even know that, so we weren't the first to do this."

Spielberg believes the Bay of Pigs incident and the Cuban Missile Crisis made the studio heads wary: "Tensions were too taut between the Soviets and the United States of America for MGM to get into the politics of the story.

"And Greg Peck's previous movie (Arabesque) was soft at the box office!"

In the new movie, which is released in America on 16 October (15), British actor Mark Rylance plays Abel. The film, which has picked up considerable early Oscars buzz, also features Amy Ryan and Alan Alda.