Pope Francis, in his latest move to simplify the Roman Catholic Church hierarchy, has severely restricted the number of priests who can receive the honorific title "monsignor".

Vatican Radio said a directive had been sent to Catholic bishops around the world outlining the new regulations for diocesan priests.

From now on, the honorific title can only be given to priests who are at least 65 years old, and thus have already given a life of service to the Church.

Until now, bishops could ask the Vatican to confer the title on priests over 35 as a distinction from the rest of the general clergy.

But critics said this often smacked of favouritism, encouraged careerism and added another layer of hierarchy to a Church that Francis says he wants to be more streamlined.

When he was the archbishop of Buenos Aires, Francis did not like to be addressed by the honorific titles "your eminence" or "your excellency" that he was entitled to.

Since his election as Pope in March, he has told clergy to see their relationship with the faithful, and not their advance up the Church career ladder, as a measure of their success as priests.

The title monsignor - literally "my lord" - dates back centuries and brings minor privileges with it, such as allowing those who have it to wear slightly different ceremonial garb to distinguish themselves.

The papal directive is not retroactive, so those who already have the title will keep it. It also will not affect those who already have the title in the Vatican by virtue of the departments they head.