BRUSSELS European leaders agreed on Friday to set the "highest standards" of nuclear safety, in part by subjecting reactors to "stress tests," to guard against crises like that at Japan's stricken Fukushima plant.
France, Germany and Spain raised the possibility of closing any of Europe's 143 reactors that fail stress tests to be held this year. Leaders at a summit in Brussels also called for Europe's neighbours to follow suit.
"We need to ensure that the highest nuclear safety standards are respected," European Commission President Jose Manuel Barroso said after a meeting, which was dominated by Europe's economic crisis and events in Libya.
"We expect (stress tests) to be universal, universal in Europe, so all nuclear sites should be subject to this assessment of safety," he added.
France, which hopes to turn the clampdown to its advantage as it tries to sell its nuclear technology overseas, sought to set an example by saying it would close reactors that failed.
"All the tests will be conducted in France, all the results will be published, and if the tests are not passed, we will immediately take the consequences, and the only consequence would be closure," French President Nicolas Sarkozy told reporters after the summit meeting.
For France, that might lead to additional pressure to prove the safety of its oldest plant, Fessenheim, close to the German border.
German Chancellor Angela Merkel and Spanish Prime Minister Jose Louis Rodriguez Zapatero said closures were a possibility for plants that do not pass muster, if additional safety measures cannot bring them up to scratch.
Europe's nuclear industry, which until recently had been enjoying the prospect of a renaissance, has found itself on rapidly shifting political terrain, with Japan's crisis still developing in the wake of its March 11 earthquake and tsunami.
European governments reacted swiftly to the situation in Japan.
Germany quickly suspended operations at seven ageing nuclear plants; Italy has announced a one-year pause on plans to relaunch banned nuclear power; Austria is demanding that nuclear power be phased out across Europe; and Bulgaria has tightened restrictions on its Belene nuclear project near a quake zone.
France, a major exporter of nuclear technology, has unexpectedly found common ground with Germany by tuning its sales pitch to the new political landscape. It has started advocating the safety aspects of its next generation reactors as it touts for business on international markets.
European Energy Commissioner Guenther Oettinger will now work on the practical details of the stress tests, so they can be put into action across the 13 of the EU's 27 member states that use nuclear power.
The tests have no legal backing, so they are effectively voluntary, but nuclear power is so controversial in Europe it would be difficult for any government to avoid them.
The findings will be made public.
The European leaders also called for swift enactment of existing plans to bury nuclear waste underground, seeking to avoid any build-up of radioactive spent fuel rods, which contributed to Japan's crisis.
Opponents of nuclear power remained critical.
"Nuclear power will never be safe," said German Green group politician Rebecca Harms. "EU-wide nuclear stress tests are little more than a strategy to take the heat off the nuclear industry."
(Additional reporting by Eva Dou, Paul Taylor and Julien Toyer; Editing by Rex Merrifield and Mark Heinrich)