Winnie Madikizela-Mandela, who was married to the former South African president from 1958 to 1996, dismissed any suggestion that the family was discussing whether to end life support to 94-year-old Mandela.
"It was nonsense to suggest we needed to take a decision to pull the tubes," Winnie told ITV News. "It was hurtful and cruel."
"It is extremely painful to see him going through what he's going through now. But it's God's wish," Winnie said.
Mandela remains in critical but stable condition at the MediclinicHeartHospital in Pretoria where he has been battling a recurring lung infection since June 8.
But daughter Zindzi Mandela told ITV that her father is alert and recognises when a new person enters his hospital room.
"The one time he did speak was to tell my mom to sit down ...because she was standing at the edge of his bed," she said.
Mandela, respected across the globe as a symbol of resistance against injustice, spent 27 years behind the bars fighting the minority apartheid regime to establish the multiracial democracy in South Africa.
Mandela had a long history of lung problems, dating back to the time when he was a political prisoner on RobbenIsland during apartheid. While in jail he contracted tuberculosis.
Mandela is revered for leading the fight against white minority rule in the African country and then preaching reconciliation despite being imprisoned for 27 years.
Mandela served as the country's first black president from 1994 to 1999.He left power after five years as president.
Mandela was awarded the Nobel Peace Prize in 1993.
He retired from public life in 2004 and has not been seen in public since the football World Cup finals in 2010.
Well-wishers were singing and saying prayers outside the hospital and at Soweto former home of Mandela, who turns 95 on July 18.
Image: Winnie Madikizela-Mandela
Photograph: Reuters
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