The auxiliary bishop of Armagh has retired because of ill health.
Gerard Clifford worked closely with Cardinal Seán Brady but has been receiving medical advice since August. He was auxiliary bishop in Armagh for 21 years and his resignation has now been accepted by Pope Benedict.
"It is with great sadness that I come to today's decision," he said.
Bishop Clifford was born near Dundalk, Co Louth, and ordained as a priest in 1967.
The former executive secretary of the Irish Catholic Bishops' Conference has worked on ecumenism, education and pastoral care in cases of "crisis pregnancy".
He has been president of the church's pro-life crisis pregnancy counselling service Cura since 2010.
Cardinal Brady, he said, had been a model episcopal colleague. "His humanity, deep faith and natural humility bear witness to the most fundamental of Gospel values."
Cardinal Brady is expected to be succeeded as Archbishop of Armagh by Monsignor Eamon Martin, the administrator of the Diocese of Derry, who was appointed co-adjudicator earlier this year.
PA