Michael Noonan (Limerick City, Fine Gael) | Oireachtas source

Our contribution to the EU budget is calculated on our GDP, as calculated by EUROSTAT. The modifications suggested by the committee under the Governor of the Central Bank to have a more transparent domestic set of numbers which would not have built in the impact of the on-shoring of IT, which ran into the GDP figures, would not be taken into account for calculations on the EU budget. The United Kingdom is a net contributor so it stands to reason that, if it moves out, the pool will be smaller by the difference between what it gets and what it contributes. A question arises as to how the adjustment will be made. Either every member state will have to pay more or the budget will be reduced by pulling back on certain services that are now funded through the EU budget. The other variable is the amount of compensatory funds upfront for which the United Kingdom will be liable. Calculations indicate this could be from as low as €33 billion or €34 billion up to over €60 billion. That would go into the pool also. It is impossible to say except that the issues the Deputy raises in his question are real and must be resolved in the course of the negotiation over the next four, five or six years.

See this speech in context