The meeting was chaired by Prime Minister Prayut Chan-o-cha.

Pongpanu said the budget set aside for preparing the venue passed the scrutiny of a mean-price-determination committee and followed negotiations with a private firm.

He was responding to criticism that too much was spent on preparations for the meeting. He said the event drew nearly 600 participants after 250 had initially been expected.

A fact-finding team was probing the controversy and if the ministry found any wrongdoers they would face penalties, he said.