The auxiliary bishop of Armagh Gerard Clifford has retired because of ill health.
Bishop Clifford who worked closely with Cardinal Sean Brady has been receiving medical advice since August.
He was auxiliary bishop in Armagh for 21 years.
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.
Bishop Clifford said: "It is with great sadness that I come to today's decision," he said.
