Ministers on both sides of the border are calling for the island of Ireland to be made a nuclear-free zone.
Social Development Minister Margaret Ritchie and Irish Environment Minister John Gormley made a joint call.
They are concerned about proposals to include nuclear power as a means of reducing the UK's carbon footprint.
"It is bad enough having a nuclear threat off our shores. We should not contemplate having one within our shores," Ms Ritchie, SDLP, said.
"The shift back towards a nuclear power energy policy in Great Britain greatly concerns me, especially given its close proximity.
'Constant threat'
"We live with the constant threat of harm from Sellafield if a disaster ever happened there and that is on top of constant radiation pollution in the Irish Sea."
She said it was vitally important all political parties signed up to a nuclear free Ireland, north and south.
Mr Gormley said he stood alongside her in saying that nuclear power was not the way forward for the island.
"There is now the potential for renewed energy in many areas such as wind and wave power," he said.
"Remember also, with nuclear power there is still the key problem of how we deal the waste."
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