National Security Council deputy secretary-general Pongsakorn Rodchompoo has been unexpectedly transferred to an inactive post in the latest move to rid the agency of all influence of former prime minister Thaksin Shinawatra.
Prime Minister Prayut Chan-o-cha exercised Section 44 of the interim charter on Tuesday to create a new position of adviser in the Prime Minister's Office for Lt Gen Pongsakorn. The shunt order took effect on Thursday when it was published in the Royal Gazette.
The position of prime minister's adviser is widely known as an inactive post for civil servants.
Pakorn Srichan-ngam, assistant to the NSC secretary-general, was promoted to deputy secretary-general under the same order.
An NSC source said the transfer was part of the campaign to eradicate ''watermelon'' soldiers from the security agency.
The term is used to describe soldiers who wear green uniforms but are viewed as "red on the inside" because they support the red-shirts, the Pheu Thai Party and Thaksin.
Lt Gen Pongsakorn was appointed to the NSC by then-prime minister Yingluck Shinawatra, moving from the Supreme Command, two years ago.
He followed the same route as Paradorn Pattanatabut, who was earlier removed from the NSC secretary general's job by Gen Prayut to a similar position as adviser to the prime minister.
Lt Gen Paradorn was also appointed to the NSC's top job from the Supreme Command when Ms Yingluck was in power.
The source said the removal of Lt Gen Pongsakorn opens a chance for Kanokthip Ratchatanan, another NSC deputy secretary-general, to lead the security agency.
With the departure of Lt Gen Pongsakorn, Mrs Kanokthip now is the most senior NSC deputy chief, a status that makes her eligible to succeed her boss Anusit Kunakorn, who will retire at the end of this fiscal year on Sept 30.
She is now tipped to become the first woman NSC secretary-general, despite competition from outsiders for the prestigious position.
The names Panitan Wattanayagorn, an adviser to the defence minister, and Panu Uthairat, secretary-general of the Southern Border Provinces Administrative Centre, are also being mentioned as possible candidates to lead the national security agency.