In its post-Fukushima review of French nuclear safety, the Autorité de Sûreté Nucléaire concluded that no plants needed to be immediately shut down, but steps should be taken as "soon as possible" to improve safety at the country's 58 reactors, said the 500-page report.
The report marks the latest sign of how the post-Fukushima environment is posing new challenges for nuclear power everywhere, including France, which garners an exceptionally high 75% of its power from nuclear energy. The ASN report comes amid a major emerging debate on nuclear power in the 2012 French presidential election.
André Claude Lacoste, the head of the ASN, said he envisions an upgrade that would likely cost "several billion euros," adding that "there will be a before and after Fukushima."
The ASN wants power giant EDF, which operates France's nuclear plants, to outline by June 30 a series of measures to reinforce "core" safety at its reactors. EDF must build diesel pumps in special bunkers to ensure all its reactors can be cooled even in the event of a massive natural disaster, the report said.
Other measures to be put in place include the creation of a rapid-response team that could be rushed to the site of any disaster and measures to reinforce the security of the pools which house spent nuclear fuel rods.
"This will take time and money," Mr. Lacoste said. "We are not asking the operator to make these investments. We are telling them to."
Mr. Lacoste said that it was difficult to imagine that the cost of this upgrade won't affect the price of generating nuclear power in France. France has lower retail electricity prices than many neighbors in Europe, but it isn't clear how the changes would affect retail prices, which are regulated in France. EDF couldn't be reached for immediate comment Tuesday.
French energy minister Eric Besson on Tuesday plans to meet with EDF and other French nuclear groups on June 9 to discuss the recommendations in the report, Mr. Besson's office said.
The aim of the ASN recommendations is to ensure that in the event of natural disaster, a reactor is supplied with water to keep it cool, that staff can continue to work and that toxic spills can be contained.
The ASN's conclusions will also be presented to the European Commission, along with the conclusions from other safety "stress tests" from across Europe. The Commission will then analyze and compare these conclusions.
The report comes as the France's political consensus on nuclear power begins to crack ahead of the 2012 Presidential elections. Recently France's Green and Socialist party formed a tentative pact and said that if they came to power, they would cut the country's share of nuclear power in the energy mix from 75% to 50% by 2025 through the gradual closure of 24 reactors.
The two political parties also said they would shut down France's oldest nuclear plant immediately, if socialist candidate François Hollande is elected president in May. The proposals have been greeted with outrage by France's ruling UMP party, who say that nuclear energy is critical for the country's economy and independence from foreign fossil fuels.
French President Nicolas Sarkozy has continued to champion nuclear power, even as neighboring countries like Germany, Switzerland and Belgium retreat.