UK and France lobby to have safety checks watered down, while Switzerland moves to phase out its nuclear power plants

Europe's nuclear power faultlines in the wake of the Fukushima disaster were exposed on Wednesday as Switzerland moved to phase out its nuclear power plants and the extent of British and French lobbying to water down nuclear safety checks was revealed.

The UK, with the backing of France and the Czech Republic, managed to have terror attacks excluded from a series of new nuclear safety tests ordered after the Japanese tsunami led to radiation leaks from Fukushima nuclear reactors in March.

The Swiss cabinet called for the decommissioning of the country's five nuclear power reactors and new energy sources to replace them. The recommendation will be debated in the country's parliament, with a decision expected in June that could see the reactors go offline between 2019 and 2034.

European regulators struck a deal on "stress tests" of how the EU's 143 nuclear power plants would withstand natural disasters, but terror attacks were reportedly excluded because of the UK argument that they lie within the purview of national security authorities and not the European commission or national nuclear regulators.

"The reason why we excluded terrorism from the tests was mainly, although not 100%, down to UK resistance," an EU official said. "The UK authorities argued that there was a difference between safety and security." The anti-nuclear green pressure group Greenpeace also accused the UK of leading the opposition to including terror attacks in the safety test simulation criteria.

Europe's divisions over nuclear power have deepened since Fukushima, with Britain and France remaining steadfast supporters, Italy shelving plans to build new plants and Germany taking steps towards a phase-out.

Plants must now prove they can withstand worse earthquakes and other natural disasters than in the past, such as a quake of magnitude 8 instead of 6, although the precise definition of "higher safety margin" will be left up to national regulators.

"One of the most important lessons to be drawn is that the unthinkable can happen – that two natural disasters can hit at the same time," the commission said, announcing the agreement.

But manmade disasters proved to be the sticking point. Scenarios such as aeroplane crashes and explosions near a plant such as from a gas container or oil tanker will be included in the stress test criteria, but, in a victory for London, the question of terror attacks is to be dealt with separately, by anti-terrorism experts and national security officials.

One UK source said: "We've always said that assessment of safety and risk is fine, but security questions should remain the preserve of national security experts. I don't think this counts as watering down the criteria at all."

The tests, to begin on 1 June, require plant operators to answer a questionnaire on the various scenarios, supported by engineering studies. National regulators will assess whether their reports are credible, and they will be subject to a peer review process by seven-member teams from the European Nuclear Safety Regulators' Group.

The commission does not have the legal power to shut down nuclear plants and is depending on citizen pressure once the results are published by the end of April 2012.