An increase in tax on industry is to be sought by the CORI justice commission in talks on a new social partnership agreement, due to begin this week.
CORI, the Conference of Religious in Ireland, also wants the introduction of new taxes on activities including land rent and financial speculation.
It claims that if the Republic is ever to have EU levels of infrastructure and social provision, it must move towards a tax-take level closer to the EU average.
Talks on a new national agreement, to replace the Programme for Prosperity and Fairness, are to formally open on Thursday.
CORI, as part of the community and voluntary social partnership group, was party to the two most recent three-year deals, including the PPF.
In a document setting out its position in advance of the new talks, it is highly critical of the failure of the social partnership process to narrow the income gap between rich and poor.
While the rise in living standards since the first agreement in 1987 has been "a good story in so many ways", it is not the whole story, it argues.
"The gap between the better-off and poor people has been widening dramatically and at an accelerating rate," it says.
It points to "major, documented problems" in a wide range of areas from adult literacy to rural exclusion. There are also serious problems in assimilating refugees, the document says.
"Asylum-seekers are denied the right to work and, at the same time, accused of 'sponging' off the State."
Despite its "weaknesses and failures", however, CORI says the social partnership process has led to a substantial involvement by civil society in governance, and it intends to remain in the process "for the time being" at least.
Calling for a widening of the tax base in any new agreement, it says that while Ireland's average per capita income is well above the EU average, its infrastructure and social provision are "far below" the EU average level.
It says an "honest debate" is needed on how improvements in infrastructure and social provision can be financed.
"No evidence of substance exists to support the contention that corporations would leave Ireland if the corporate tax rate were higher, at 17.5 per cent, for example, as against the current target of 12.5 per cent."
CORI argues that the likelihood of budget deficits from 2003 onwards, and the relatively low tax take in Ireland, suggest a need to broaden the tax base.
A land rent tax and a tax on currency transactions could lead to substantial reductions in income tax, it claims.
"Eco-taxes" on the consumption of water, fuel and fertilisers, as well as the disposal of waste, would also help shift the burden away from income tax.
CORI also has proposals on a wide range of other areas, including healthcare, education and housing, which it intends to bring to the negotiating table.
It wants the establishment of a national housing authority, as well as an independent national agency to oversee and implement a national policy on homelessness.