MELBOURNE (REUTERS, AFP) - Lawyers for ex-Vatican treasurer Cardinal George Pell on Tuesday (Sept 17) filed an appeal to Australia's High Court in a final bid to overturn his conviction for sexually abusing two 13-year-old choir boys, the High Court said.

Pell is seeking leave to appeal against the state of Victoria's Court of Appeal ruling which upheld his conviction on five charges of abusing two boys at St Patrick's Cathedral in the late 1990s when he was archbishop of Melbourne.

The former Vatican treasurer who once helped elect popes, last month lost an appeal in Victoria state's Court of Appeal in a landmark decision that saw the judges split in a 2-1 verdict.

Pell and his supporters have staunchly maintained he did not commit the crimes, which came to light after one of the victims went to police when the other died of a drug overdose in 2014.

There is no guarantee that the High Court will agree to consider Pell's case.

Australia's most senior judges will now deliberate on whether to allow the appeal to proceed, a process that could take months.