The Government will run a higher surplus in the public finances than forecast at budget time, based on higher levels of Corporation Tax.
Speaking in Dublin, Minister for Finance Paschal Donohoe said this was part of preparations for what he called the "clear and present danger" that current high levels of Corporation Tax will not last.
Exchequer returns published today show a surplus of almost €1.45 billion in the first eleven months of the year - with the State taking in 2.7% more than was anticipated at the start of the year.
Almost all of that - €1.41 billion - is accounted for by a stronger-than-expected take of Corporation Tax.
Speaking after a keynote address on the economy this afternoon, Mr Donohoe said running budget surpluses would prepare Ireland for a potential fall-off in Corporation Tax in the future.
The minister announced new targets to reduce Ireland's national debt over time. However he said levels of capital investment would be maintained.
He also said he would not make any contribution to the Rainy Day Fund until it was clear Ireland no longer faced the threat of a hard Brexit.
Aside from Corporation Tax, the latest Exchequer figures show Income Tax €175m (0.8%) ahead of expectations, while VAT was €171m (1.1%) lower than anticipated.
Excise is currently running €14m (0.3%) lower than predicted, while Stamps are down €109m (7.3%) on what was forecast in the Government's budgetary plans.
Earlier, the Minister said that the Government expects to run a better than expected budget surplus of 0.4% of gross domestic product this year following another surge in corporate tax receipts.
Corporate tax receipts have more than doubled since 2012, mainly boosted by the country's large cluster of multinational firms.
Last year it hit a record high of €10.4 billion which the Finance Department until recently expected to moderate.
Instead, the receipts almost hit a fresh annual high with a month to spare after they were €700m ahead of target in November alone, Mr Donohoe said.
November is the largest collection month of the year when around a quarter of all corporate tax returns are made, he added.
The Finance Minister said last month that he expected corporate tax receipts to top €11 billion this year and rise again in 2020 before plateauing and at some point falling as new global rules under consideration on how and where big internet firms pay tax are introduced.
Speaking at the Institute for International and European Affairs today today, the Minister also set a number of medium-term targets to build up the country's fiscal buffers,
He is seeking to achieve surpluses of at least 1% of GDP by 2022 and to reduce the state's debt as a percentage of national income to 85% by 2025, assuming a disorderly Brexit does not derail the economy.
If Britain does not leave the European Union with a deal to smooth its exit, Mr Donohoe said the debt reduction target would be increased to 90-95% of national income or debt-to-GNI*, a measure unique to Ireland to gauge its open economy.
The debt-to-GNI* ratio, which strips out some globalised activities which skew more traditional measures of economic activity, currently stands at around 100%.
Paschal Donohoe warned that the ultimate outcome of Brexit - even if Prime Minister Boris Johnson ratifies his divorce deal after next week's parliamentary election - remains highly uncertain.
"A disorderly exit either without ratification of the revised Withdrawal Agreement or at the end of the transition period in 2020 remains a distinct possibility in the not-too-distant future," he said.