But the move, which also applies to other religious rituals, is controversial and leading figures have already expressed misgivings.

A papal decree said priests should now meet requests by the faithful to hold mass in the traditional Church language, which had widely been dropped after the Second Vatican Council in the 1960s.

"In parishes where there is a stable group of faithful who adhere to the earlier liturgical tradition, the pastor should willingly accept their request to celebrate the Mass according to the rite of the Roman Missal published in 1962...," said the decree.

"The pastor, having attentively examined all aspects, may also grant permission to use the earlier ritual for the administration of the Sacraments of Baptism, Marriage, Penance and the Anointing of the Sick, if the good of souls would seem to require it," it added.

The virtual abandonment of the Tridentine mass after the Second Vatican Council in 1965 was one of the causes of a breakaway led by French Archbishop Marcel Lefebvre in 1970.

The move was to encourage the greater use of the mass in local languages, one of a series of reforms made by the council in a bid to modernise the Church.

Traditionalists say the Tridentine mass, named after the town of Trento, now in northern Italy, is more spiritual and historically authentic than the modern version.

French bishops secretly approached the pope late last year to voice their concerns about his then apparent readiness to revive the Tridentine mass.

Cardinal Jean-Pierre Ricard, chairman of the French bishops' conference, said in November that differences with followers of Lefebvre were not only liturgical, but also theological, dealing with religious freedom, ecumenism, inter-religious dialogue and politics.