The Labour Party has accused the Government of "throwing in the towel" on pursuing a legal challenge to shut the Sellafield reprocessing plant.
Labour spokesman on nuclear safety, Emmet Stagg, said the international legal case seeking the closure of Sellafield has been official Government policy for many years but now Minister for the Environment Dick Roche had "admitted that it has effectively been abandoned".
He claimed the Government had left Ireland exposed to "potential catastrophe" from an accident or terrorist attack on the plant. Mr Stagg made his comments as details were announced of an 86-day anti-nuclear walk from Dublin to London next month. It is being organised by the US-based peace organisation, Footprints for Peace.
"The Government must now state whether or not the closure of Sellafield remains official policy," Mr Stagg said.
Mr Roche rejected Mr Stagg's claims and reaffirmed the Government's opposition to the Sellafield plant.
"Using every legal and diplomatic means, the Government will continue its fight for the safe and orderly closure of the facility," he said. "No government has worked harder to achieve this objective."
Mr Roche said that, in considering future legal action, the Government would be influenced by European Commission action on the issue, and by the advice of the Attorney General. "There is no softening of our opposition to this facility or to our pursuit of the means to ensure its safe and orderly closure."
The "Towards a Nuclear Free Future" walk will start in Dublin on May 12th and will finish in London on August 6th, the anniversary of the bombing of Hiroshima.
Leaving Dublin, the walk will follow a path along the northeast coast, and walkers will meet with communities concerned by pollution from the Sellafield reprocessing facility.
The group will take the ferry to Scotland and walk up to the Faslane Trident nuclear submarine base. The walk will continue to the Sellafield facility in Cumbria and on to locations associated with weapons production.
Kerrie-Ann Garlick from Footprints for Peace said she hoped the walk would raise public awareness of the suffering caused by the nuclear industry.
"We would like as many people to join us for as long as they can - a single step, an hour, or the whole way, to carry the message of a nuclear-free future," she said.
Footprints for Peace has organised peace walks in the US, Australia and Japan over the past 15 years.