Pope Francis has called on the Catholic Church to "act decisively" to root out sexual abuse of children by priests and ensure the perpetrators are punished, the Vatican has said.

The pope asked Archbishop Gerhard Ludwig Mueller, the head of the Vatican department that deals with sexual abuse, to "act with determination" in those cases, the Vatican said in a statement on Friday.

The pontiff asked for "stepped-up measures to protect minors and help those who were subjected to such violence in the past".

In a meeting with Mueller, Francis said that combating the abuse was important "for the Church and its credibility", the statement said.

It was the first official word on the issue from the pope, who was elected on March 13 to succeed Benedict XVI, whose papacy was marred by relentless paedophilia scandals with tens of thousands of victims over several decades.

The statement noted that the policy followed "the line established" by Benedict XVI, who was the first pope to apologise to victims and called for zero tolerance against sexual abuse by priests.

Francis inherited a Church mired in problems and a major scandal over priestly abuse of children.

'Action, not discussion'

A victims' group, the Survivors Network of those Abused by Priests (SNAP) said the statement did not go far enough and criticised it for saying that the Church's stance against sexual abuse was "a continuation" of the line wanted by Francis' predecessor, Pope Benedict.

"Action, not discussion, is needed," SNAP said in a statement.

SNAP and other victims groups say there is much still to be discovered about how the Church behaved in the past and want more bishops who were aware of abuse to be held responsible.

The cases of abusive priests burst into the spotlight more than a decade ago with a cascade of scandals rocking the Church worldwide, from Ireland to the United States, from Australia to Benedict's native Germany.

The Vatican says it continues to receive around 600 claims against abusive priests every year, many of them dating back to the 1960s, 1970s and 1980s.

Sexual abuse by priests has often been coupled with cover-ups by their superiors, typically by transferring them to other parishes.

The Catholic Church in many countries has been forced to set up new guidelines to deal with cases of past abuse, prevent new cases, report abuse to police, and stop potential abusers from entering the priesthood in the first place.

Source: Agencies