The new investment will include a boost for research into nuclear safety.

The French nuclear giant Areva is developing the fourth generation of reactors. France gets 80% of its electricity from nuclear power.

Earlier this year neighbouring Germany, Switzerland and Italy voted against nuclear power, following Fukushima.

As president of the G8 and G20 industrial groups, Mr Sarkozy has been pushing for an international standard on nuclear safety.

"We are going to devote a billion euros to the nuclear programme of the future, particularly fourth-generation technology," Mr Sarkozy told a news conference.

"We are also going to release substantial resources from the big loan to strengthen research in the sphere of nuclear safety."

He stressed his government was still investing "massively" in renewable energy. He announced 1.35bn euros of investment for that sector.