The Minister for the Environment, Mr Cullen, will raise the discovery of radioactive waste in farmed salmon at this week's OSPAR Commission in Bremen, Germany.
"It is clear for many years now that radioactive discharges from Sellafield result in contamination of the Irish marine environment," he said.
He was responding to news of research carried out on behalf of Greenpeace that found low levels of Technetium-99 (Tc-99) in farmed Scottish wet and smoked salmon.
The salmon is sold in British supermarkets Sainsbury's, Asda, Safeway, Waitrose, Tesco and Marks and Spencer.
Tc-99 is a by-product of Magnox fuel reprocessing which is carried out at the Sellafield nuclear plant in Cumbria.
The Food Safety Authority, however, has said there was no reason for consumers to be alarmed.
Mr Alan Reilly, deputy chief executive of the FSA, said although the authority was aware of the levels of Tc-99 in the Irish Sea, and while it would prefer it was not there, "there was no reason for consumers to stop eating salmon".
He said a person would need to eat about 700 portions of salmon per year for there to be any adverse health effect.
The Irish Salmon Growers' Association welcomed reassurances from the FSA, adding that salmon farmed in Ireland was "reared only on the west coast of the country and fed from sustainable fish stocks".
The salmon growers' executive secretary, Mr Richie Flynn, said consumers should be "fully aware of the origin of all their food, particularly fresh produce such as fish".
Tesco Ireland said no Scottish salmon was sold in their outlets and it was all sourced in the west of Ireland.
Marks and Spencer, however, confirmed all the wet salmon sold in their four outlets here was Scottish. A spokeswoman said there was no plan to withdraw it from sale. "There is absolutely no health risk and we don't want to create a scare issue where there is none," she said.
However, alarm has been expressed at the news of radioactive waste in salmon. Green Party MEP, Ms Nuala Ahern, said the facts were "both dangerous and shocking".
"I am calling on the Government to make sure that our deep concern at radioactivity levels in the Irish Sea and our desire for the permanent closure of Sellafield are articulated at the OSPAR conference - the first since 1998."
Labour Party spokesman on nuclear safety, Mr Emmet Stagg, said the British had "totally reneged" on the commitment given by the Deputy Prime Minister, Mr John Prescott, to reduce discharges from Sellafield.
"The sad reality is that they have increased dramatically and are set to double over the next few years," he said.
Mr Eoin Ryan TD said the fact that traces of waste had "ended up on the shelves underlines the threat Sellafield represents to people on both sides of the Irish Sea.
"Even before any further increases we know that Sellafield is the main source of artificial radioactivity in Dublin Bay and right along our east coast."