Screenwriter William Nicholson wishes Nelson Mandela could have seen 'Long Walk To Freedom' before his death on Thursday (05.12.13).

The 65-year-old Oscar-nominated writer penned the adaptation of Mandela's autobiography of the same name and he would have loved the South African civil rights activist and former president - who was imprisoned between 1962 and 1990 for his objection to the apartheid regime - to have seen the full film which stars Idris Elba.

Speaking to BANG Showbiz just hours before Mandela's death at the UK royal premiere of the movie in London's Leicester Square yesterday, he said: ''I wish he could see it, Mandela, but he can't because he is too ill. But it's still [happening] while the man is still among us.

''It's finally in it's best possible form which, I suppose, is what happens when you finally come through because amongst other things we've got Idris and he is sensational and I am so pleased about that.''

Nicholson admits it's been a tough road to get the film made but he feels he had a ''duty'' to produce the biopic.

He explained: ''It started in 1997 - a long time ago. I did not think we would ever get here, we've been through so many directors, so many actors, so many packages have and fallen apart. [It was] extremely difficult.

''I have a duty to respect him and show him as a real person. That's really difficult. ... You'll have to see the film yourself, he's a womaniser, he's a violent guy, he's a guy who likes sharp suits and fast cars, and he's a remarkable peace keeper.''

Sadly, the premiere came on a poignant night, as the 95-year-old world leader - who had been in poor health for some time - passed away at his home in South Africa just hours after the film's stars and crew walked the red carpet.

Producer Anant Singh, who is a third generation South African of Indian descent, told of the huge responsibility of giving the story of Mandela's life the justice it deserves.

He explained: ''I think trying to tell a story which starts as an eight-year-old and ends as an 84-year-old is a huge journey. It is something I could not take lightly. As a South African, I have to do it, and do it right, and so it has taken us a while.''