Cape Town, June 30 (IANS) US President Barack Obama, currently on an official visit to South Africa, Sunday toured Robben Island off Cape Town to pay tribute to his "personal hero" -- ailing former South African president Nelson Mandela.
The visit was part of Obama's three-day official trip to South Africa, his second to the country, but first as US president, Xinhua reported.
The 94-year-old Mandela has been hospitalised in Pretoria for the past three weeks for a recurring lung infection.
Obama, accompanied by his wife Michelle and daughters Malia and Sasha, took a helicopter ride to the museum on Robben Island, where Mandela spent 18 years in a prison cell.
The US president refrained from visiting Mandela in Pretoria, but met Mandela's family members instead.
The White House said the decision was made in accordance with the wishes of Mandela's family. Obama himself said he did not want to be "obstructive" when Mandela was critically ill.
Mandela's condition remains critical but stable, according to South African President Jacob Zuma, who issued the latest update on Mandela's health Saturday.
Zuma said the government hoped that Mandela would be out of hospital soon.
During his visit, Obama repeatedly lauded Mandela's contributions to South Africa and the world.
Mandela managed to transform South Africa and inspire the world, Obama said.
"Think about 27 years in prison. Think about the hardships and struggles of being away from family and friends," the US president said.
"Reflecting on his years in prison, Nelson Mandela wrote that they were dark moments that tested his faith and humanity but he refused to give up," Obama said at the University of Johannesburg Soweto Campus Saturday.
"We join the people of the world in sending our prayers to Madiba and his family because he still inspires us all," he said.