Los Angeles - U2 frontman Bono has paid tribute to Nelson Mandela by writing an essay on the late anti-apartheid revolutionary.
The 53-year-old singer, who along with his bandmates contributed the song Ordinary Love to the biopic Mandela: Long Walk to Freedom - based on the former South African President's autobiography of the same name - penned an extended piece on the anti-apartheid leader, who died on Thursday night aged 95, after hearing of his passing.
In 1051-word essay for Time magazine entitled The Man Who Could Not Cry, Bono - who has helped try to end global poverty for a number of years - described Mandela as a "forceful presence" in his life since 1979.
He wrote: "As an activist I have pretty much been doing what Nelson Mandela tells me since I was a teenager. He has been a forceful presence in my life going back to 1979, when U2 made its first anti-apartheid effort.
"Over the years we became friends. I, like everyone else, was mesmerised by his deft maneuvering as leader of South Africa.
"It certainly fell to Mandela to be great. His role in the movement against extreme poverty was critical. He worked for a deeper debt cancellation, for a doubling of international assistance across sub-Saharan Africa, for trade and private investment and transparency to fight corruption.
"Without his leadership, would the world over the past decade have increased the number of people on Aids medication to 9.7 million and decreased child deaths by 2.7 million a year? Without Mandela, would Africa be experiencing its best decade of growth and poverty reduction? His indispensability can't be proved with math and metrics, but I know what I believe..."
Several other stars from the music industry have also paid tribute to the late leader - who battled to overcome apartheid in South Africa and win equal rights for black people, which saw him jailed between 1962 and 1990 - including Rihanna.
She wrote on Instagram: "One of the greatest men who's ever lived!!! #LegendWe will never forget the things this man has taught us, and we will never truly comprehend the level of strength that it took for him to endure many of his years!! Thank you #Mandela (sic)"
She added on Twitter: "#NelsonMandela you made your people proud!! We'll always love you for it! (sic)"
LL Cool J tweeted: "Nelson Mandela. What a difference one person can make. #RestEternally (sic)"
Singer Aretha Franklin said: "What a sad day that such a great man has passed on and moved on up a little higher. Most extraordinary was how he rose above his being imprisoned and exalted himself above apartheid and hatred to unite the country, an unbelievable example of humanitarianism and courage."