HBO's long-gestating miniseries 'Criminal Justice', which was originally slated to star late James Gandolfini, will not feature Robert De Niro anymore, it has been revealed.

De Niro, who signed on to replace the late 'Sopranos star', has exited the seven-hour miniseries due to a scheduling conflict, with O Brother, Where Art Thou's John Turturro taking over the lead role, the Hollywood Reporter reported.

'Criminal Justice', a US adaptation of Peter Moffat's 2008 BBC drama of the same name, was originally developed as a series at HBO. The network passed on the pilot in February 2013, only to revive it as a limited series last May.

It is being produced by HBO in association with BBC Worldwide Prods. and Film Rites. De Niro's Tribeca Films banner will exit the production.

The story follows Jack Stone (Turturro), an ambulance-chasing lawyer who becomes involved in a case defending a young man accused of murdering a girl on New York's Upper West Side.