Under canon law all bishops must offer to resign at the age of 75. The retirement of Bishop O’Brien, who will be 75 in August, has been accepted for reasons of health, the office said.
He had been an auxiliary of Westminster since 1977.
Commenting on his retirement, Cardinal Cormac Murphy-O’Connor said: “Bishop Jim has always been on the side of the poor as an advocate for justice, both as the chair of the Justice and Peace Commission of the Bishops’ Conference of England and Wales, and later as head of the Diocese’s department for ecumenism, interfaith and justice & peace work. I always greatly valued his counsel and friendship, and will continue to be grateful for both in the years ahead.”