Minister for Foreign Affairs Micheál Martin has said it could be January 2010 before the new European Commission is in place.
Speaking in the Dáil, Mr Martin said the Council would adopt a list of Commission nominees, which would then be subject to a vote of the European Parliament.
The new Commission would then be appointed by the European Council.
Minister Martin said European Commission President Jose Manuel Barroso had indicated that the final decision on the allocation of portfolios to new commissioners must await the appointment of the new High Representative, one of the two new posts created under the Lisbon Treaty.
The Minister said it was the intention of the Government that the Irish nominee to the post of Commissioner, Máire Geoghegan-Quinn, would secure a good portfolio.
Earlier, the Minister rejected an accusation from Fine Gael's Pat Breen that the Government had been lukewarm in its support for former Taoiseach John Bruton, whose name had been associated with the post of European President.
Minister Martin said the Taoiseach had made known to his counterparts the high regard in which he held Mr Bruton and had made direct approaches to others seeking support for his nomination.
Mr Martin pointed out that there were a number of very strong candidates emerging from the European People's Party, of which Mr Bruton is a member.
