Obama arrives in South Africa

US president Barack Obama has arrived in South Africa, embarking on the second leg of his three-country African journey.

The visit comes at a poignant time, with former South African president and anti-apartheid hero Nelson Mandela ailing in a Johannesburg hospital.

Mr Obama is expected to meet with US consulate staff in Johannesburg today.

Tomorrow he is to meet with South African president Jacob Zuma. The two men are then expected to hold a joint news conference.

Mr Obama said today he was not certain whether he would be able to see Mr Mandela, who is gravely ill, during his visit.

Following his visit to South Africa, Mr Obama is scheduled to go to Tanzania. He travelled to South Africa from Dakar, Senegal.