Johannesburg - US Secretary of State of State Hillary Rodham Clinton was set to touch down Sunday in the oil-rich state of Angola on the third stage of her seven-country Africa tour.

Clinton was en route to Angola Sunday morning from South Africa, where she spent two days meeting with political, business and community leaders in order to improve relations that faltered during the presidencies of George W Bush and Thabo Mbeki.

Under the new US and South African administrations, relations would move "to a higher level," President Jacob Zuma said after meeting Clinton on Saturday in Durban.

Zimbabwe featured prominently in her talks with Zuma and Foreign Minister Maite Nkoana-Mashabane.

Clinton called for more support for reformists in Zimbabwe and made clear that targeted US sanctions against President Robert Mugabe and his allies would remain, despite repeated calls from South Africa for the sanctions to be lifted.

She also visited former presidents and Nobel laureates Nelson Mandela and FW de Klerk, toured health and housing projects and addressed business leaders about trade opportunities, with the US and with other African countries.

On Sunday, Clinton is scheduled to meet with Angola's foreign and energy ministers and host a roundtable meeting with the National Assembly in Luanda before talks on Monday with the president of 30 years, Eduardo dos Santos.

Angola is a staunch ally of China, a rival of the US in the battle for influence and business in Africa.

Angola rivals Nigeria as Africa's largest oil producer and is China's biggest supplier of the commodity.

The US gets only about 7 per cent of its oil from the country, where it backed right-wing rebels against the Soviet-backed ruling MPLA during a 27-year civil war that broke out after Angola gained independence from Portugal in 1974.

The war ended with nearly half a million dead in 2002.

After Angola, Clinton continues her tour in Democratic Republic of Congo, Nigeria, Liberia and Cape Verde. She began her tour in Kenya on Tuesday.(dpa)