Vatican finance chief Cardinal George Pell said Thursday that he would return to Australia to try to clear his name after becoming the most senior Catholic cleric to be charged with criminal offences linked to the Church's long-running sexual abuse scandal.

Pell was ordered to appear on July 18 at court in Melbourne for a preliminary hearing on multiple sexual assault charges related to offences allegedly committed decades ago, when he was a senior cleric in his homeland.

Pope Francis granted Pell a leave of absence, making it clear the cardinal would not be forced to resign his post as head of the Vatican's powerful economic ministry.

Claiming he had been the victim of a campaign of "relentless character assassination", Pell vowed to beat the charges and return to work in Rome.

"I am looking forward finally to having my day in court. I am innocent of these charges," the 76-year-old said. "They are false. The whole idea of sexual abuse is abhorrent to me."

In a supportive statement, the Vatican noted Francis's respect for the Australian's "honesty" and "energetic dedication" to his work on Church financial reform.

"The Holy See expresses its respect for the Australian justice system that will have to decide the merits of the questions raised," the statement said.

"Cardinal Pell has openly and repeatedly condemned as immoral and intolerable the acts of abuse committed against minors; has cooperated in the past with Australian authorities... and finally, as a diocesan bishop in Australia, has introduced systems and procedures both for the protection of minors and to provide assistance to victims of abuse."

But Marie Collins, an Irish survivor of clerical sex abuse, said Francis should never have appointed Pell, given his failure to address abuses carried out by priests under his charge.

While Pell deserves to benefit from the presumption of innocence over his own conduct, "it has been proved he is guilty of the appalling mishandling of cases of abuse when still in place in Australia and causing untold pain to the victims in those cases," Collins wrote on her blog.

Story continues

- Multiple complainants -

Vatican watchers said it was unlikely Pell would ever return to his post given the time it will likely take for his case to come to trial and be completed.

The cardinal is already a year past the age at which Holy See employees are supposed to retire and suffers from a heart condition.

Pell was missing from a mass Francis gave for five new cardinals on Thursday and will not appear at any public events in Rome before his departure for Australia, the Vatican confirmed.

Police in the Australian state of Victoria said Pell had been charged with "historical sexual assault offences".

Deputy Commissioner Shane Patton said there were "multiple complainants" but provided no details as to the precise nature of the charges, or the age of the alleged victims.

A lawyer for two unidentified men who had made abuse claims against Pell said they were "over the moon".

"It's been very difficult for them to stick their neck out," the lawyer, Ingrid Irwin, told Melbourne's Herald Sun newspaper. "To come out against someone who is second to God, in some people's minds, has caused all sorts of problems for them."

SNAP, a US-based network of survivors of clerical abuse, praised the Australian authorities' action.

"We hope it will inspire other countries to follow in their footsteps," spokeswoman Joelle Casteix said. "Sexual abuse thrives when it is allowed to flourish in secrecy."

- 'Mucked up' -

The announcement of the charges against Pell coincided with the final stages of Australia's Royal Commission into Institutional Responses to Child Sex Abuse, ordered in 2012 after a decade of pressure to investigate widespread allegations of institutional paedophilia.

The commission has spoken to thousands of survivors and heard claims of child abuse involving churches, orphanages, sporting clubs, youth groups and schools.

Pell appeared before the commission three times, once in person and twice via video-link from Rome. In one hearing, he admitted that he "mucked up" in dealing with paedophile priests in Victoria state in the 1970s.

The Pell charges stem from investigations by a police task force into allegations emanating from the Royal Commission and from a state parliamentary inquiry.

The commission said in February that seven percent of Catholic priests were accused of abusing children in Australia between 1950 and 2010 but that the allegations were never investigated.

It found that 4,444 alleged incidents of paedophilia were reported to church authorities and, in some dioceses, more than 15 percent of priests were perpetrators.

Widespread abuse has also been uncovered in recent decades in other countries with large Catholic communities, badly tarnishing the standing of the Church in Ireland and North America in particular.

Francis came to office four years ago promising zero tolerance and an end to Church cover-ups of the kind portrayed in "Spotlight" the 2015 Oscar-winning drama about the Boston Globe's exposure of unpunished abuse in its local diocese in the early noughties.

But critics say he has made little headway, leaving the Church still reluctant to hand paedophile priests over to civilian authorities.