An Indonesian court has overturned convictions against a Canadian and an Indonesian who were jailed for 10 years each for sexually abusing children at a prestigious Jakarta international school, their lawyer said Friday.

School administrator Neil Bantleman, who also holds British nationality, and teaching assistant Ferdinand Tjiong were sent to prison in April after they were found guilty of abusing three young children.

The pair maintained their innocence, and received backing from the Jakarta Intercultural School and many parents at the institution in a case criticised as being fraught with irregularities.

A lawyer for the pair, Hotman Paris Hutapea, told AFP that the High Court in Jakarta had overturned the convictions.

"The content of the decision is to free my clients. There is no proof," he said, without saying when the decision was handed down.

Hutapea was heading Friday to the South Jakarta District Court, which handed down the original decision to jail the men, to pick up documents and start the process of getting his clients released.

However prosecutors could still appeal the High Court decision to the Supreme Court.

The news came just days after a court rejected a $125-million sex abuse lawsuit against the school, which was previously known as the Jakarta International School.

The men's supporters had claimed the decision to pursue them was linked to the multi-million-dollar civil suit brought by the mother of an alleged victim.

The scandal began last year with claims that cleaners committed abuse, before allegations were levelled at Bantleman and Tjiong.