The Government can halve the rate of public spending cuts and still meet its requirements under the EU/IMF bailout deal, community organisations have argued.
Seventeen groups involved in the voluntary sector said increased taxes targeting the wealthier would be a much fairer way to repay national debts.
Fr Sean Healy, speaking on behalf of the umbrella grouping Community and Voluntary Pillar, made his call in a presentation to TDs and senators ahead of the Budget.
"That would get a much fairer outcome," he said.
"We believe it's possible, it's do-able, you can in fact protect the poor and vulnerable despite the difficulties of the time. It's a question of choices."
Fr Healy said the Government is currently trying to reduce its borrowing by cutting two euro in public spending for every one euro raised in increased taxes.
The Community and Voluntary Pillar wants this ratio reversed to one euro cutbacks for every two euro in tax hikes.
But they have warned against income tax increases and called instead for tax breaks benefiting the well-off to be scrapped.
Fr Healy said it was the Government's duty to protect the vulnerable and the bailout troika confirmed during their last trip that Ireland was free to adjust the terms of its agreement as long as the financial outcome remains the same.
The social campaigner said the current arrangements required too big a set of changes with a harsh impact on the vulnerable at too fast a pace.