Idris Elba based his Nelson Mandela role on his late father.

The 41-year-old actor plays the anti-apartheid revolutionary, who died last night (05.12.13) aged 95, in biopic 'Mandela: Long Walk to Freedom', and admits he looks very similar to his late father, who recently passed away from lung cancer aged 76, when portraying Mandela as an old man.

When asked how he felt when he saw himself with white hair and wrinkles while playing the former South African President at a later stage of his life, he replied: ''Funny, because that's how we designed the older Mandela to assimilate how I would look, and ironically I looked just like my old man. I designed my Mandela on my dad.''

Idris admits his father got emotional when he watched his son take on the iconic role because he knew it would be one of the last times he would see him on the big screen.

He added to The Sun newspaper: ''He cried. He was so emotional, because I think he must have known, if I'm really honest about it.

''He must have thought it was one of the last times he was going to see one of my really big performances.

''It's a sad film and now, when I think about it, it must have been emotional for him. He must have known. We were all in denial. It was a great moment to share.''

Idris attended the Royal Premiere of 'Mandela: Long Walk to Freedom' in London's Leicester Square last night alongside his co-star Naomie Harris - who plays Mandela's ex-wife Winnie - as well as Prince William and Duchess Catherine, and the 'Luther' actor admits he did ''so much'' research before he started filming.

He told BANG Showbiz: ''I was more of a journalist than an actor when I first got the role [as Mandela]. I didn't know as much as I'd like to about him, there is so much to learn.

''Especially about his aura, about the way people feel about him because you can't really act that. You just have to have some understanding of it, so that's what I did.''

Mandela's daughters Zindzi and Zenani Mandela were also at the premiere and they immediately left the screening of the movie - which is based on the late leader's 1994 autobiography of the same name - upon hearing about their father's death.

A spokesman for the Nelson Mandela Foundation said: ''They received the news of their father's passing during the screening and immediately left the cinema.''