French President Nicolas Sarkozy pledged Thursday to defend and bolster France's nuclear sector, and warned that an opposition-backed proposal to wind down nuclear power production would shut factories and damage the economy.

Sarkozy's strong backing for a sector that provides France with 75% of its electricity needs came after the Socialist Party and the Greens agreed to cut nuclear's share in France's energy mix to 50% by 2025, if their candidate Francois Hollande were to win May's presidential election.

"Quitting this energy or cutting authoritatively its share in our energy mix without a substitute with the same characteristics would produce considerable damages to France's industry," Sarkozy said in a speech marking the third anniversary of the Fonds Strategique d'Investissement, or FSI, a sovereign wealth fund he set up to support strategic sectors of the French economy.

"The price of power is one of the rare advantages over our competitors," Sarkozy said.

The debate on nuclear power has gained traction in
France , which hosts 58 reactors and is the world's second-largest nuclear operator behind the U.S. , after the Japanese Fukushima incident in March led Germany to shut its nuclear plants and Italy to cancel plans to revive the industry after a quarter-century moratorium.

For decades, the nuclear industry has enjoyed bipartisan support in
France , which embraced atomic energy in the 1970s in order to reduce its exposure to oil and as a way to strengthen its independence. Sarkozy was adamant that shouldn't change, and pledged part of the EUR20 billion FSI to strengthen suppliers of equipment to the nuclear industry in order to better structure the sector and encourage exports.

"All French political parties have backed this unprecedented national effort," he said. "It's not politics, it's not the right, it's not the left, it's not the opposition, it's not the majority: it's
France ."

Sarkozy also said the FSI, which has bought shares in companies ranging from shipyards Chantiers de l'Atlantique to toy-maker Meccano, should strengthen its support of the aeronautical and medical equipment industries. A regional network will be created to foster investment in small- and medium-sized businesses, and an initial EUR350 million will be given to regions and other public institution to invest in SMEs.

Still, Sarkozy cautioned that there is only so much the FSI can do to stem the hemorrhage of industrial jobs.

"It's not the job of the state to support businesses that are no longer viable," he said, blaming the half-million shrinkage in the headcount of industry jobs between 2000-2007 on the 35-hour working week, which has "permanently sapped" the country's competitiveness. Instead, policy should be directed at protecting industry from the ravages of global financial markets, and by hostile foreign takeovers.

"The state must mitigate the terrible shortsightedness of markets that destroy value, jobs and skills in an irremediable way," Sarkozy said. "I won't let big French companies fall prey to predatory buyout offers."