The Vatican is preparing to introduce legal procedures to establish the responsibilities of bishops and Catholic hierarchy found guilty of protecting priests who have sexually abused children, a spokesman said on Wednesday.

The issue of accountability was discussed in the presence of Pope Francis by the C9, the group of senior cardinals who advise him.

Victims' groups accuse the Church, the Vatican and the pope of refusing to take action against hierarchy who have turned a blind eye to paedophile acts. In some cases, the priests are simply moved to different areas or different jobs.

The group of senior cardinals said the rules "were not sufficiently clear to deal with this kind of problems".

They called for "routes to be explored to proceed on the legal front against abuses of power and omissions" by bishops and other Church hierarchy, Vatican spokesman Federico Lombardi told a press conference.

He said the procedures would be put in place "in a diligent manner".

US cardinal Sean O'Malley, a member of the C9 and head of a committee for the protection of minors set up by the pope, told his committee of his concerns during the meeting.

A working group established by the C9 committee met O'Malley at the weekend to discuss the controversial nomination of a Chilean bishop, Juan de la Cruz Barros, who is suspected of having shielded a paedophile priest.

The members of the sub-committee have called for the pope to change his mind.

They told O'Malley that "the process of naming bishops who have an understanding of the protection of childhood is of a primary importance".

The Vatican has so far said it sees no reason to revere Cruz Barros' appointment.