MELBOURNE (Reuters) - Australia’s High Court on Wednesday agreed to hear a final appeal from Vatican treasurer George Pell over his conviction for sexually assaulting two teenaged choir boys.

Pell, who is in jail serving a six-year sentence handed down by a lower court in March, turned to the High Court after a first appeal upheld his conviction.

The High Court appeal hearing, to be presided over by a full bench of five or seven judges, will be held in March 2020 at the earliest, a court spokesman said.

Pell, the most senior Catholic official worldwide to be jailed for child sex offences, will remain in prison while his lawyers prepare for the High Court appeal.

In a brief statement, the Vatican said it “acknowledges” the court’s decision “aware that the Cardinal has always maintained his innocence”.

It reiterating trust in the Australian justice system and said the “Holy See reaffirms once again its closeness to those who have suffered because of sexual abuse on the part of members of the clergy”.

Pope Francis has declined to comment on the case until the appeals process is exhausted.

Pell was convicted by a jury in the County Court of Victoria last December of abusing two 13-year-old boys at St Patrick’s Cathedral in the late 1990s when he was archbishop of Melbourne. Under the six-year sentence he received in March, he will be eligible for parole in October 2022, when he will be 81.

A first appeal was heard by the state’s Court of Appeal, where judges upheld his conviction by a 2-1 majority in August.

Pell’s lawyers took the case to the High Court on the basis the Court of Appeal was wrong to have found that the jury’s verdict was not unreasonable. Lawyers also argued the majority judges had erred in shifting the burden of proof to the defence to show that it would have been impossible for Pell to have committed the offences.

The High Court on Wednesday ordered Pell’s lawyers to file their arguments for appeal by Jan. 8, with the Crown prosecutors’ response due on Feb. 5.

Pell no longer has any position in the Vatican but remains a cardinal.

For Pell to be dismissed from the priesthood, the Vatican’s Congregation for the Doctrine of the Faith would have to find him guilty following a separate canonical trial or a shorter process.