British nuclear operators face being sued for billions of pounds by the Irish government and Irish victims of any radioactive damage they cause under legal changes to be introduced this year.
Politicians and campaigners in Dublin have long complained about the impact, both historical and potential, of the UK's civil nuclear programme close to its shores, with particular focus on the safety record of Sellafield. The Cumbria site is located less than 100 miles from Ireland's east coast.
Greenpeace has warned that the dumping of the reprocessing plant's liquid waste has made the Irish Sea among the most contaminated waters in the world, even though Ireland itself produces no nuclear energy. Irish fishermen have been angered by catches of unsaleable mutated fish and by findings that they have been exposed to low-level radiation.
However, Ireland's government and environmental campaigners have struggled to make international legal headway to clampdown on Britain's nuclear activity, soon to be expanded with a new fleet of power plants starting with Hinkley Point C in Somerset. In 2006, for example, the European Union blocked ministers from taking a case to a United Nations tribunal in an attempt to force the closure of Sellafield.
Legal experts say that Ireland's case will be radically strengthened when amendments to the Paris Convention on Third Party Liability in the Field of Nuclear Energy finally come into force this year, having been originally proposed in 2004. The UK is a signatory to this treaty and the changes will allow anyone in Ireland affected by a nuclear accident that originates at a British site to seek up to £1bn in damages from the plant's operator in the High Court.
Previously, only governments and victims from signatory nations to the treaty could sue each other, and even then claims were capped at £140m per incident. From this year, countries such as Ireland that are not part of the convention will be able to seek damages under its terms, while British victims will be able to claim nine times more than they were previously allowed.
Ian Salter, an international legal expert in nuclear issues at lawyers Burges Salmon, said: "If a country has no nuclear installations in it, then they will benefit from the changes. Someone in Ireland could bring a claim to a court in the UK in a way that they couldn't before.
"It is a much more straightforward process. This makes the situation much simpler for the victim and [it] could be used by a national state."
The fallout from major nuclear accidents spreads far from their original locations. Radiation from the 1986 Chernobyl disaster in the Ukraine spread across Europe and had long-term effects; last year, thousands of jars of Italian organic jam were found to be contaminated as a result of the accident.
A spokesman for Ireland's energy department said that ministers and officials there were "aware" of the amendments and its implications. The Nuclear Decommissioning Authority, which owns 19 sites in the UK, said that accident clean-up costs are covered by insurance.
The Irish anti-nuclear campaigner Brian Greene commented: "These changes sound interesting and I would think that our government would be pursuing them."