Taoiseach Enda Kenny has insisted that ratifying the European fiscal treaty will ensure Ireland has access to emergency funds.
Tanaiste Eamon Gilmore also said that while money may still be available from the International Monetary Fund (IMF) even if the public rejects the treaty, a "No" vote would be too risky as the terms for funding would be uncertain.
As campaigning for and against the deal got under way, with Environment Minister Phil Hogan signing the referendum order, the Taoiseach said it is important Ireland has an insurance policy in place.
"The line of confidence for investment into Ireland is exceptionally strong," said Mr Kenny. "We need to keep that line of investment very strong for jobs and for opportunities for the future."
Fine Gael will on Tuesday officially kick off its campaign for a "Yes" vote in the referendum on May 31. The Labour Party launched its campaign in favour of the treaty on Monday while Fianna Fail is expected to do the same later in the week.
The treaty will see tighter budgetary rules from Europe and penalties imposed on member states that fail to meet them. Those in favour have claimed that refusing to support the fiscal deal would result in Ireland being cut off from Europe and denied emergency funds should it require a bailout down the line.
Meanwhile, former Fianna Fail deputy leader Eamon O Cuiv broke ranks with the party when he launched his own campaign for a "No" vote in the referendum.
The Galway TD, who resigned from his deputy seat in February after clashing with leader Micheal Martin over the party's pro-Europe stance, said the Government and Fianna Fail's reasons for supporting the deal were weak.
He told RTE Raidio na Gaeltachta the Government has other choices to help the country return to growth. He also warned that even if it accepts the treaty, it will be unable to meet its terms if it is to carry the bank debts.
Opposition parties Sinn Fein and the United Left Alliance have launched their own anti-treaty campaigns, claiming it will bring about further austerity and plunge Ireland into another economic crisis.