LUANDA : US Secretary of State Hillary Clinton on Sunday shifts the focus of her Africa trip to business as she works to ensure a steady oil supply from key producer Angola and counter China's growing influence.

The top US diplomat was due to make a one-day visit to the southern African nation, which vies with Nigeria as the continent's biggest oil producer but where two-thirds of the population lives on less than two dollars a day.

Clinton was going to Angola "to strengthen that relationship with one of Southern Africa?s emerging countries, a country which has enormous economic potential," said Johnnie Carson, her top Africa aide.

He dismissed talk of rivalry with China, saying that was a "Cold War paradigm."

China, hungry for resources to fuel its rapidly growing economy, has been ramping up investment in Angola and other African nations, often raising controversy as Beijing puts little focus on human rights and good governance.

Angola is now China's largest supplier of crude oil. But it is also a key provider to the United States; Angola sold 19 billion dollars in exports to the US market last year, 90 percent of it oil.

Clinton will meet in the former Cold War battleground with veteran President Jose Eduardo Dos Santos, oil industry executives and Oil Minister Jose Botelho de Vasconcelos, currently president of the Organisation of Petroleum Exporting Countries (OPEC).

The stop is the most business-oriented on her seven-nation tour of Africa, after she worked to revive close ties with regional power South Africa and pressed for good governance and political reforms in Kenya.

The focus in Angola is unusual for Clinton, who has made the fight against climate change a top priority. Aides said she wanted to highlight that the US government was also committed to meeting its giant energy requirements.

But Washington is also looking to help Angola broaden its economy. Clinton will sign a memorandum with oil giant Chevron to support agriculture.

Francisco da Cruz, a former Angolan diplomat who was based in Washington in the 1990s and now head of the US Angola Chamber of Commerce, was hopeful that Clinton's visit would further move relations forward from the Cold War years.

"We hope that this visit will create a better environment in relations between the two countries," he told AFP. "It will allow for the opening up of new opportunities for American companies to invest in this market in partnership with Angolan companies."

"It has been a long process and we have seen different phases and now we can say both countries have a very close and fruitful relationship," he said.

The former Portuguese colony was torn by a 27-year civil war that ended in 2002, with the US backing UNITA (Union for the Total Independence of Angola) rebels against the Soviet- and Cuban backed government of Dos Santos.

UNITA is now the political opposition and appealed for Clinton to bring the US message of good governance here, charging that Angola was suffering from "institutionalised corruption," human rights violations and unequal distribution of wealth.