Obama 'deeply humbled' by visit to Mandela's Robben Island jail

US President Barack Obama who is on an African holiday reportedly visited the Robben Island jail where Nelson Mandela was held for 18 years in the apartheid era.

Obama expressed being 'deeply humbled' after visiting the bleak cell where Mandela spent years and was forced to undertake hours of back-breaking labour, BBC reports.

According to the report, Obama wrote in the guest book of the jail about how he and his family were 'deeply humbled' to stand where men of such courage faced down injustice and refused to yield adding that the world is grateful for the heroes of Robben Island, who remind that no shackles or cells can match the strength of the human spirit.

Mandela's long history of lung problems can be traced to the tuberculosis he contracted in the cell, which he attributed to the dampness of his cell.

Obama gave a keynote address at the University of Cape Town, the same venue where US Senator Robert Kennedy gave his famed 'ripple of hope' speech giving inspiration to those fighting the racially divisive policies of apartheid rule and linked their struggle with that of the US civil rights movement.

Obama said that Mandela showed that one man's courage can move the world.

The report further said that, Obama has announced 7 billion dollars, five-year initiative to double access to electricity in sub-Saharan Africa, in partnership with African countries and the private sector.

Although, Obama did not meet the ailing Mandela but he met his family in private, the report added.