Opus Dei head Javier Echevarria has died at the age of 84 after leading the arch-conservative Catholic movement for two decades. Critics have long accused it of having excessive influence within politics and the church.
The Madrid-born Echevarria died of a lung infection in a Rome clinic, said a spokesman for the German branch of Opus Dei, Hartwig Bouillon on Tuesday.
The Rome-based movement is believed to have 2,000 priests but most of its 92,000 members are lay or non-clerical believers, located predominantly in Spain, Argentina and Chile.
Echevarria became the leader or prelate in 1994. Opus Dei (God's Work) was founded in 1928 and has a reputation for secretiveness, devout loyalty and gender segregation.
The German branch on its website said his designated replacement was auxiliary vicar Fernando Ocariz. Confirmation was still required at an Opus Dei congress and from the pope.
Last July, when the Vatican revamped its communications strategy, former American Fox News Rome-based journalist Greg Burke became Pope Francis' official spokesman.
Burke, who was reportedly a member of Opus Dei, replaced Father Federico Lombardi, a Jesuit like Francis, who for a decade had been Vatican spokesman.
The media reorganization followed a series of scandals and leaks involving the Vatican and its representatives in various nations.
ipj/msh (Reuters, AP, dpa)