Cardinal Sean Brady has offered his resignation as Archbishop of Armagh.
In a statement, the Catholic Primate said that his coadjutor Archbishop Eamon Martin would replace him as head of the church here as soon as Pope Francis accepts his resignation.
Cardinal Brady turns 75 tomorrow.
"Last month I offered my resignation to Pope Francis in accordance with the requirement of Canon Law," he said in the statement.
"I did so in anticipation of my 75th birthday which I will celebrate tomorrow.
"On January 18, 2013, Pope Benedict XVI acceded to my request for episcopal support and Archbishop Eamon Martin was appointed as Coadjutor Archbishop of Armagh.
"This means that as soon as Pope Francis accepts my resignation, Archbishop Eamon will become Archbishop of Armagh and Primate of All Ireland.
"Archbishop Eamon has been warmly welcomed into the diocese.
"He has worked tirelessly in getting to know its priests, religious and lay faithful, as well as by becoming involved in every aspect of the life of the Church in Armagh and beyond."
"I look forward to the day when my resignation will be accepted and when Archbishop Eamon will take over as Archbishop, a position for which, I believe, he is excellently prepared."