The Taoiseach would be prepared to nominate the European Parliament President, Mr Pat Cox, to be Ireland's next European commissioner if it emerges that the Munster MEP could secure the Commission presidency.
Mr Cox is seen as having an outside chance of becoming a serious contender for the top Commission job should the 25 EU member-states fail to agree on any of the main contenders.
The Commission president is to be chosen by agreement among member-states in June, some three months before they must nominate their commissioners.
A spokesman for the Taoiseach said yesterday that Mr Ahern believed that "if any Irish man or woman has a chance of becoming president of the European Commission, he would support them 100 per cent."
Mr Cox has said he will announce in the European Parliament today whether he will seek re-election to the European Parliament in the June elections.
The Taoiseach and the Tánaiste have had some discussions on the commissionership, although no decision has been reached.
A spokesman for Ms Harney said yesterday: "Mr Cox possesses the requisite skills to be a commissioner, as do a number of potential candidates."
He would not say whether the Tánaiste was backing Mr Cox or any other candidate for the Irish commissionership.
Ms Harney and Mr Cox have now repaired their working relationship which was exceptionally poor during and after the contest for the PD leadership in which both were candidates 10 years ago.
The two worked closely together during the recent controversial EU debate on stem-cell research, and Government sources say Mr Cox has been a useful conduit of information to both the Taoiseach and Tánaiste on EU matters in recent times.
However, should Mr Cox not secure the top Commission job in June, the Taoiseach is expected to choose Ireland's next commissioner from within Fianna Fáil. He or she does not have to chosen until the autumn.