Richardson's was partowned by Irish Fertiliser Industries and, while its employees' pensions were fully secured when the former state company was wound up, their colleagues north of the border lost most of their retirement benefits along with their jobs.

"We'll have to up the political pressure significantly to get the Dublin government to put its hands in its pockets, " said Barry Duddy of the UK's Pensions Action Group, who worked for Richardson's for 25 years. "Everyone's standing outside the ring hoping that somebody else will pay up. It's extremely difficult to embarrass them [the Dublin government] on this, issue because there are no votes north of the border."

Enterprise minister Micheal Martin has ruled out a rescue package, telling the Dail last year: "While I have the utmost sympathy for the plight of the membersf I am satisfied that the Irish government does not have any obligations in respect of the shortfallf and I do not see any basis on which we could reasonably be expected to make good the shortfall."

However, it is understood that Nigel Dodds of the Democratic Unionist Party, whose north Belfast constituency was home to the Richardson's plant, is continuing to put pressure on Taoiseach Bertie Ahern for some form of financial contribution.

The UK government has already refused to compensate victims of workplace pension scandals. But it is being challenged by the Pensions Action Group. Four of its members, including 64-year-old Harry Bradley, who spent 27 years at Richardson's, are seeking a judicial review of Westminster's hard-line position on pensions. The case is sue to be heard on 7 February.