CAPE TOWN - An epic film based on the autobiography of former South African president Nelson Mandela will soon be released, it was learned here on Friday.

The news came as Mandela spent his 48th day in hospital for treatment of a recurring lung infection. He remains in a critical condition although his health has showed "sustained improvement," the government said earlier this week.

The world premiere of Mandela: Long Walk to Freedom is scheduled for the 38th Toronto International Film Festival in September, according to producer Anant Singh.

Singh said in a statement he was delighted that the film was selected for the prestigious festival.

After the premiere, the film will be shown in South Africa on November 28.

"We always believed that Toronto is the perfect platform to launch the film to international audiences," Singh said. "We are pleased to continue a 15-year association with the festival which has featured many of our South African productions, including Red Dust and the Oscar-nominated Yesterday.

"The Toronto Film Festival is unique as it allows us to present the film to both industry people and regular film-goers in Canada. "

Mandela is a long time admirer of Singh and his work and when the film rights were awarded a few years ago he said then that he had personally opted for him.

The film, directed by Justin Chadwick, portrays Mandela's amazing legacy, revealing both visually and historically, the life of Mandela and the freedom movement -- a story of soaring inspiration and human suffering.

The film is authorized by Mandela, with the Nelson Mandela Center of Memory having provided research and archival support.

Three actors play Mandela in the film: Siza Pini plays the eight-year-old Mandela, Atandwa Kani plays him at 16, and Idris Elba plays the remaining years.