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US president Barack Obama travels to Cape Town on Sunday where he will be visiting Robben Island.
The US president will also pay tribute to Nelson Mandela when he delivers a keynote speech at the University of Cape Town.
On Saturday, Obama met the family of his "inspiration" Nelson Mandela but was unable to see the anti-apartheid legend who remains critically ill in hospital.
Obama and his wife Michelle called Mandela's wife Graca Machel, and then privately visited several daughters and grandchildren of Mandela, to offer support and
prayers.
Meawhile, Obama affirmed his country's commitment to enhancing co-operation and trade with South Africa and its neighbours.
"Africa is on the rise and South Africa is always at the forefront of trends in Africa," Obama said at a joint media brieing with President Jacob Zuma in Pretoria.
"I see South Africa as critical to one of my top priorities on this trip and that is to promote trade and investment that helps unleash growth here in Africa and ultimately will benefit the United States of America."
Obama pledged support for the extension of the African Growth and Opportunity Act (Agoa), which expires in 2015.
Agoa allows Southern African countries to ship certain products to the US tariff-free.
"Today, almost all of South Africa's exports to the US - 98 perent already enter our market duty-free, Obama said.
"I told President Zuma I want to renew, but also improve and update the Agoa, so we are generating more trade and more jobs."
But, Obama said he had to first demonstrate to US companies the
benefits of investing or exporting to SA.
"We're gonna make sure our trade negotiators have a serious conversation about how we get a win-win formula that delivers jobs and opportunities for peope here in SA and also in the US," he said.
South Africa's role in peace-keeping efforts was also lauded.
"We thank SA for being a leading force in the African Union from promoting peace between Sudan and South Sudan to econmic cooperation across the continent."
Zuma welcomed Obama to the country despite protests against his two-day visit.
He said Obama was visiting Africa at the "right time".
"We are pleased to be working with you [Obama] today with a common goal of expanding trade and relations between our two countries," said Zuma.
"Mr President you are visiting Africa at the right time...Africa is rising...It is the second fastest growing region after Asia and has become an attractive market for investment."
Zuma said he was committed to strengthening the US-Africa partnership.
In 2011, total trade with the US was in excess of R130 billion, with South Africa enjoying a trade surplus of around R18bn. South Africa was also the US's biggest market in Africa, accounting for US7.3bn of American exports.
