Krisadang Nutcharus, one of the organisers, revealed on Saturday that Thammasat's directors had barred Parit Chiwarak and Panusaya Sithijirawattankul and human rights lawyer Arnon Nampa from the discussions at the Si Burapha Auditorium.
The reason behind the ban was not revealed.
“The decision makes us see the cowardice of the directors. We are holding this forum to hear different political opinions, views and perspectives. Banning them is unacceptable,” said Krisadang.
Meanwhile, the Free People group has announced it will hold its next rally on October 14 at Democracy Monument, to mark the October 14, 1973 mass uprising against military dictatorship.