Saga is targeted at the over 50s

Jagger's company, Jagged Films, produced the movie, adapted from Robert Harris' book set in 1943.

It tells the dramatic tale of the British codebreaking triumphs by the experts at Bletchley Park in Buckinghamshire during the Second World War.

Their exploits are believed to have shortened the war by at least two years.

Hijack

Jagger told Saga Magazine about his efforts to stave off attempts by US movie-makers to hijack the film and turn it into a story about an American triumph.

He said: "We could not get the American money to make this unless we changed it to an American story and how can you translate this to a place like Philadelphia."

The film stars a host of British talent including Kate Winslet, Dougray Scott and Saffron Burrows.

Jagger added: "We've had some of the best technicians and film crews around for years.

Code-breaking may have shortened the war

"We are now getting a crop of strong young actors coming through who are acceptable to the Americans.

"I am not against having an American actor in any film so long as they are good. Where it goes wrong is having to employ an American who is no good, just to keep the financiers happy."

Jagger, 58, has a solo album due out in November, collaborating with such artists as U2's Bono, Lenny Kravitz and rap star Missy Elliott.

Enigma received its UK premi�re at the Edinburgh Film Festival and will go on general release in September.