The Taoiseach is holding talks with Northern Ireland First Minister the Rev Ian Paisley in his Ballymena constituency today.
They are expected to discuss political and economic developments in Northern Ireland and increasing cross-Border co-operation.
The Taoiseach said he was honoured to visit the north Antrim heartland of the DUP leader.
"I do not believe even a year back it could have been envisaged we would have been together here," Mr Ahern said. "It is an honour to be here with the First Minister to talk about progress."
Mr Paisley joked that Mr Ahern and his entourage had held a prayer meeting in their helicopter hoping that they would not be pelted with snowballs by him - a reference to his famous protest when former taoiseach Sean Lemass visited Stormont
When asked about welcoming the Fianna Fáil leader to his constituency he quipped: "What I am saying is he is in under my control. This is a good day for work.
"It is a good day for our province. It is a good day for the whole of Ireland because we need help from outside.
We cannot live on our own."
They will meet again next week at the Dublin Chamber of Commerce AGM where Dr Paisley has been invited to be a guest speaker.
The engagement is the latest visit to the Republic by the DUP leader since the Assembly was restored in Stormont last May. The Taoiseach invited Dr Paisley to the historic Battle of the Boyne battle site in Co Louth in July where the DUP leader presented a 17th-century musket to Mr Ahern .
Last October, Dr Paisley addressed the Trinity College Historical Society in Dublin and also attended an event in the Royal College of Physicians in the city in November.