Vatican City  - The Vatican announced Tuesday the retirement of Nigerian-born Cardinal Francis Arinze, who was touted by many as a strong candidate for the papacy ahead of the 2005 conclave that eventually elected Benedict XVI.

Benedict has accepted the "for age limits" resignation of Arinze as prefect of the Congregation for Divine Worship and the Discipline of the Sacraments, the Holy See said in a statement.

Archbishop Antonio Canizares Llovera of Toledo, Spain, takes over as head of the congregation, which deals with regulations governing the use of liturgical texts and the administration of church sacraments.

The 76-year-old Arinze acted as a close advisor to the late pope John Paul II who, impressed by the then archbishop of Onitsha, Nigeria's handling of Muslim-Christian tensions in his African homeland, placed him in charge of the Vatican's interfaith dialogue department in 1979.

Arinze's high Vatican rank fuelled speculation that he could become the first modern-era "black pope."

Roman Catholic bishops and Vatican office bearers are obliged to retire upon reaching the age of 75, but may remain longer until a successor is named.

There are no age limits on candidates being elected pope, but only cardinals who have not yet turned 80 are allowed to vote in a conclave.