Prime Minister Prayut Chan-o-cha ordered a probe into private schools refusing to return fees to students for services that weren't delivered because classes were held online.

"These schools should have known what fees weren't used during the online study period such as food, transport, computer and internet services, and study tours," Prayut said.

Education Minister Nataphol Teepsuwan discussed the possibility of lowering the fees private schools were collecting since they able to organise normal classes for their students.

During the recent resurgence of Covid-19, schools were ordered to close throughout January and conduct classes online instead.

"The schools closed for the whole of January, so there will be certain collected fees that have not been used and those sums must be returned to parents," said the education minister.

Mr Nataphol said he had already ordered schools to prepare lists of fees received during the pandemic which could be waived and returned.

The schools had agreed to provide details of returnable fees within 15 days, he said.

However, the minister would not order private schools to refund a percentage of January's tuition fees, as demanded by some parents.