South Africa has signed a nuclear power agreement with France, the government said on Friday, three weeks after it reached a similar deal with Russia as part of Pretoria's first tentative steps towards building up to 9,600 MW of nuclear power.

The Sept. 20 agreement, which Russia touted as a $10 billion contract to build power plants, took many South Africans by surprise, compelling officials to clarify that it was in fact just the early stages of a long procurement process.

Energy officials also stressed that other intergovernmental agreements - with France, China, South Korea, the United States and Japan - were likely to follow.

A statement from President Jacob Zuma's office on Friday described the deal with France as "cooperation in the development of peaceful uses of nuclear energy", but did not provide details.

South Africa has one nuclear power station that provides around 5 percent of its 42,000 MW of installed generating capacity. Nearly all the rest comes from coal.

It has plans to build six new nuclear plants by 2030, providing 9,600 MW of power, although there are concerns the costs - estimated at between 400 billion and 1 trillion rand ($36-$89.9 billion) - could be unaffordable.

Opponents of nuclear also argue that it will take too long - a decade or more - to build the power stations, making them irrelevant to solving the immediate electricity supply crunch that Africa's most advanced economy is facing.