Dublin MEP Gay Mitchell has confirmed he is to seek the Fine Gael nomination for the Presidential election.
It is understood Mr Mitchell only made the final decision to run in the past 24 hours.
A former Minister of State for European Affairs, Mr Mitchell topped the poll in Dublin in the last European elections.
He said: 'My political conviction is informed by a Christian Democratic ethos, based on four pillars: rights and responsibilities, enterprise and social justice.
'I want to advance this ethos in public life and I see the Presidency as another way of doing so.
'My belief is that this ethos, if applied sensibly, will help equip Ireland to overcome some of our present economic and ethical difficulties and make us a country which others will want to emulate.'
The only other confirmed candidate for the Fine Gael nomination is Mr Mitchell's fellow MEP Mairead McGuinness.
However, there has also been speculation about the plans of former PD and European Parliament President Pat Cox, who has applied to join the party.
Former Taoiseach John Bruton has ruled himself out of contention.
The nominee will be chosen by an electoral college, with the parliamentary party having 70% of the vote, councillors 20% and the National Executive 10%.