The European Commission's plans to introduce a Common Consolidated Corporate Tax Base (CCCTB) across the European Union could destroy Ireland's tax take, UCC economist Seamus Coffey has warned.
Speaking before the Oireachtas Finance Committee on the proposals, Coffey said: "It is not unduly pessimistic that Ireland cold lose up to 50% of our current corporation tax base if the CCCTB is to be introduced."
The Government is opposed to the plans, which include making companies pay tax in countries where sales are made rather than where they are controlled.
With corporate tax receipts set to amount to more than €7bn for this year, that would mean €3.5bn less money in the State's coffers.
Coffey also noted that, as well as seeing Irish-based companies forced to pay some of the tax currently paid here elsewhere, it could change corporate behaviour, including where they set up.