The Taoiseach travels to Brussels today for an EU summit on the financing of enlargement.
EU leaders will be haggling over who pays for the enlargement of the Union at their summit with a dinner this evening.
The leaders will agree formally that the 10 candidate countries (Poland, Hungary, the Czech Republic, Slovakia, Slovenia, Latvia, Lithuania, Estonia, Cyprus and Malta) are eligible to join the EU in 2004 and will agree how to implement institutional changes outlined in the Nice Treaty.
But four countries, led by Germany, are refusing to endorse a financial package for the candidate countries that includes extending direct payments to farmers in Central and Eastern Europe.
Germany said it will not approve extending direct payments until other members agree to phase out the subsidies after 2006. France and Ireland are leading the opposition to any link being made between financing enlargement and reforming the Common Agricultural Policy.
Mr Ahern will also discuss Northern Ireland with the British Prime Minister Mr Tony Blair tomorrow morning.