The junta has turned down the red shirts' request to hold a press conference on their views on the constitution draft scheduled on Sunday afternoon.
Col Winthai Suwaree, spokesman of the National Council for Peace and Order (NCPO), said on Saturday the NCPO decided not to allow the United Front for Democracy against Dictatorship (UDD) to exchange views with the media on the charter draft.
"We have to stick to the existing guideline [of banning] any activity that may potentially cause confusion, adversely affect unity, peace and order, or can possibly impede us from following the roadmap," he said.
So far, some people have asked for permission to talk to the press but they do so personally, not as a political group, he said.
He was possibly referring to a similar activity held by Suthep Thaugsuban, chairman of the Muan Maha Prachachon Foundation, a rival group of the UDD, earlier this week.
"We also found several UDD members have already expressed their opinions publicly on numerous occasions. We found what they said was political discourse aimed at smearing the NCPO or influencing people to have a negative view about us by using incomplete facts. Such behaviours were the factors of our consideration," he added.
Besides, he continued, the UDD did not give details on what they planned to talk or who the speakers would be and the junta needed this information if it were to approve the request.
"The NCPO has opened channels to listen to opinions from all parts of society. UDD leaders have made their views known through these channels all along. The media already know their viewpoints," he concluded.