Cardinal George Pell arrives at County Court in Melbourne, Australia, February 27, 2019. AAP Image/Erik Anderson/via REUTERS

MELBOURNE (Reuters) - The defense lawyer for Australian Cardinal George Pell, a former top Vatican official now in custody pending sentencing for sexually abusing 13-year-old boys, apologized on Thursday for controversial comments he made about the assault.

The former Vatican treasurer is the most senior Catholic cleric to be convicted for child sex offences. He was found guilty in December of five offences committed in the 1990s, but the verdict was only made public this week when the court lifted a suppression order on the case.

Robert Richter, who presented Pell’s defense in court, had tried to argue that his client’s offences were at the low-end of the scale, at one point saying it was “no more than a plain vanilla sexual penetration case” where the child did not willingly take part, an argument quickly dismissed by the judge.

In a statement to the Australian Broadcasting Corporation, he said he had made a “terrible choice of a phrase”.

“In seeking to mitigate sentence, I used a wholly inappropriate phrase for which I apologize profusely to all who interpreted it in a way it was never intended,” Richter said.

“It was in no way meant to belittle or minimize the suffering and hurt of victims of sex abuse, and in retrospect I can see why it caused great offence to many.

“I hope my apology is accepted as sincerely as it is meant and I will never repeat such carelessness in my choice of words which might offend.”

The 77-year-old Pell had been on bail throughout the court proceedings. Bail was revoked on Wednesday and he was taken into custody. He is due to be sentenced on March 13.