A "critical milestone" has been reached in South Africa's plans to build new nuclear power stations, the presidency announced on Wednesday.

The stage was now set to start the preparatory stage for the procurement process that would be undertaken in line with the country's legislation and policies, it said in a statement.

This followed the signing of intergovernmental framework agreements with the United States, South Korea, Russia, France, and China.

"These agreements set out potential frameworks of co-operation that each country foresees where or how they can participate in South Africa's new nuclear build programme," the presidency said.

Government had also, over the past two months, successfully concluded so-called nuclear vendor parade workshops with these same countries.

"The nuclear vendor parade workshops entail vendor countries presenting their nuclear technology offerings."

South Africa is planning to build 9600MW of nuclear power capacity.

"The conclusion of this vendor parade marks a significant milestone in the government pre-procurement phase for the roll-out of the nuclear new build programme."

The presidency said government intended ensuring energy security for the country through the nuclear new build programme as an integral part of the energy mix.

The programme would create massive infrastructure development, and stimulate the local economy.

"[It will] enable the country to create thousands of high-quality jobs for engineers, scientists, artisans, technicians and various other professions; develop skills and create sustainable industries; and catapult the country into a knowledge economy," it said.

Critics of the project say it is unaffordable and will cost the country upward of R1 trillion.