Irish actor Michael Fassbender has been forced to drop out of the upcoming spy movie 'Tinker, Tailor, Soldier, Spy' because of scheduling conflicts with his new blockbuster 'X-Men: First Class'.

The Daily Mail reports that Fassbender has been replaced in the film by 'Inception' star Tom Hardy, who will now play the character Ricky Tarr.

Based on John Le Carré's best-selling spy thriller of the same name, 'Tinker, Tailor, Soldier, Spy' tells of the hunt for a mole within the British intelligence service and was previously made into a classic TV series starring Alec Guinness.

Gary Oldman will play Guinness' character, George Smiley, in the film and the cast also includes Colin Firth, Ciarán Hinds, Jared Harris and Benedict Cumberbatch.