THE most senior Vatican cleric to be implicated in the Roman Catholic Church child abuse scandal has returned to Australia to stand trial on multiple charges of sexual assault from years ago.

Cardinal George Pell, Pope Francis' top financial adviser, avoided waiting media when he arrived at Sydney Airport on a flight from Singapore.

Australia's senior Catholic had declined to comment to media who questioned him in Singapore at the weekend as he made his way home from Rome.

The 76-year-old cleric is due to appear in a court in the Victoria state capital Melbourne on July 26 on what Victoria Police described as multiple counts of "historical sexual assault offences".

There is no statute of limitations on such crimes in Australia. Police said there were multiple complainants, but have released no other details.

When police announced the charges last month, the cardinal vowed to fight the allegations, saying: "The whole idea of sexual abuse is abhorrent to me."

He has taken a leave of absence as Vatican finance czar to return to Australia to clear his name and has said he intends to return to the Vatican to continue his work as a prefect of the church's economy ministry.

Pope Francis thanked Cardinal Pell for his "honest" work and collaboration, and said he would wait for Australian justice to run its course before making a judgment himself.

For years, the cardinal has faced allegations that he mishandled cases of clergy abuse as archbishop of Melbourne and, later, Sydney.

But more recently, he himself became the focus of a clergy sex abuse investigation, with Victoria detectives flying to the Vatican to interview him last year.

It is unclear what the criminal charges against the cardinal involve, but two men, now in their 40s, have said that he touched them inappropriately at a swimming pool in the late 1970s, when he was a senior priest in Melbourne.