He could hardly be described as Nelson Mandela’s spitting image, but when the British actor Idris Elba arrived at the South African premiere of Mandela: Long Walk To Freedom on Sunday, there was some of the awe and adulation usually reserved for the great statesman himself.

“You can see the sweat! No pressure?” joked Elba, feeling the heat of countless camera phones as he wiped perspiration from his forehead. “South Africans love their Madiba and it’s a massive responsibility to bring him alive in the best possible way.”

Playing Mandela is an acting Everest that stars including Morgan Freeman, Danny Glover, David Harewood, Terrence Howard, Clarke Peters and Sidney Poitier have attempted to scale, but none, perhaps, have quite reached the summit. Elba, who grew up in Hackney, east London, has already earned the praise of Mandela’s family.

Asked on the red carpet about the daunting task of nailing Mandela’s accent, Elba replied: “I just wanted people to recognise him when they heard the sound and say, ‘That’s Madiba!'”

The star of The Wire and Luther had almost missed the black-tie event in Johannesburg after he suffered a severe asthma attack on a South Africa-bound plane and was hospitalised. But he took another flight just in time to witness in person how South Africans judge his portrayal of the nation’s father figure in the £22-million biopic.

The premiere was held a few miles from the suburban home where Mandela (95), remains in a critical condition after spending three months in hospital with a recurring lung infection. “He’s probably watching this on the news as we speak,” Elba mused. “This is very special.”

Mandela’s absence made it a poignant gathering of his closest family, friends and comrades who mingled with their cinematic counterparts. Winnie Madikizela-Mandela, his second wife, sat beside Elba during speeches at a champagne reception. Greeted by ululations, she told the hundreds of guests: “I’m just as excited as all of you are. Thank you for coming to join us in revisiting that turbulent journey that brought us here today. I have no words to describe the translation that Anant [Singh, the producer] came up with of that painful past.”

She added: “Let us just all go and sit back and revisit our history. The importance of this is that we should remember where we come from and that this freedom was hard earned and it was won at a very heavy price. We’re here to celebrate not only comrade Madiba but all the men and women who perished in the liberation war.”

Mandela’s third and current wife, Graca Machel, was also present but declined to be interviewed. They were joined by the new British and US ambassadors, the Nobel laureate Nadine Gordimer and long-time friends of Mandela including Ahmed Kathrada, a fellow prisoner on Robben Island, and the lawyer George Bizos, who defended Mandela from a possible death penalty half a century ago. “It brings back the memories,” Bizos said.

Singh said a smiling Mandela had asked “Is that me?” when he saw a picture of Elba made up with grey hair and wrinkled face and wearing one of his trademark Madiba shirts. “I said, Madiba, you really think it’s you?” Singh recalled.

Elba sat through more than five hours of makeup before filming began, said Singh, who spent 16 years on “a very rocky road” searching for funding, the right script and the right director. For the latter role he eventually settled on Britain’s Justin Chadwick, who admitted: “I was resistant. I’m from Manchester, I’m not from South Africa.”

Winnie is played by another Briton, the Skyfall actor Naomie Harris, but the rest of the cast are South African. The film traces the life of the anti-apartheid hero from his childhood in the rural Eastern Cape to his imprisonment on Robben Island and his election as the country’s first black president in 1994.

Mandela’s daughter Zindzi, who attended a previous private screening, said: “When I watched the movie it was a very emotional moment for me. I found it quite therapeutic. It made me confront many emotions that I’d buried and refused to acknowledge. Honestly it was very difficult … At the same time, the love that kept the family together comes through in the film. And the fact that my father left … and my mother continued the struggle.”

The 53-year-old added: “There is a scene where my sister and I are left alone at home because my mother has been locked up and my sister is looking after me, like trying to make us breakfast and so on. It made me weep and weep because it was so true. And we had those moments of loneliness where we found there is nobody for us and it was very bleak and no hope of anybody coming to our rescue. And just that scene alone took me to the various episodes in my life where I just felt the absence of a father, of a mother and of a normal family life.”

In a recorded message for the event, South Africa’s president, Jacob Zuma, said: “A life of inspiration. That is the best way to describe Madiba … He became an inspiration to the world as a freedom fighter, a statesman and a man of principle.

“We will tell the story of this wonderful human being, this great African for many, many generations. We are privileged to have lived in the time when he put his stamp on history. So I welcome the premiere tonight, the first public showing on African soil, of the film Long Walk to Freedom.”

The biggest cheer of the night was reserved for Elba when he joined other cast members on stage and said: “What an amazing turnout, we’re very proud. This story is so much bigger than me, than any of us, and when we were given the task to bring this story to life it was under the guidance of Justin and Anant. I’ve never worked with such a committed set of actors. In true spirit, these are my comrades.”

The movie will be released in South Africa on 28 November and the UK on 3 January.