Australia's bishops must lead an urgent delegation to Pope Francis seeking changes to some of the church's most fundamental views on women, celibacy, governance and the handling of child sex cases, according to Australia's peak Catholic reform group in a call to arms to Catholics across the country.

In an open letter sent to all parishes, Catholics for Renewal has urged bishops and archbishops not to "defer to the Holy See", or wait for the recommendations from the Royal Commission into Institutional Responses to Child Sexual Abuse, before acting on serious issues identified by the commission that contributed to the child sexual abuse crisis.

Catholics for Renewal president and former senior Australian government bureaucrat, Peter Johnstone, said bishops needed to be prepared to urge Pope Francis to require mandatory reporting of all child sex abuse allegations to police and immediately appoint women to the church's highest ranks.

"The appointment of women would be revolutionary, but I would argue the Pope could do that tomorrow and that would be a catalyst for forcing ultra-conservative bishops to realise they've got no choice but to get on board," Mr Johnstone said.