The cabinet's roster remains unchanged, appointing Piyapong Jiwattanakulpaisan as the new Permanent Secretary of Transport, replacing the retiree, and paving the way for Chayut Lohakit, a key figure from Buriram's influential faction, to become Director-General of the Department of Highways. A major executive reshuffle is imminent, with a direct appointee of the Prime Minister set to become Director-General of the Marine Department.
Reporters from the Ministry of Transport stated that during the cabinet meeting on 11 August 2026, the cabinet resolved to appoint Mr. Piyapong Jiwattanakulpaisan, Director-General of the Department of Highways, as the Permanent Secretary of the Ministry of Transport, replacing Mr. Chayatham Promsorn, who will retire on 30 September 2026. This appointment makes Mr. Piyapong not only the youngest Director-General in the department’s history at just 50 years old but also the youngest Permanent Secretary of Transport.
Regarding this appointment and nomination, it is noted that Mr. Piyapong maintains close ties with the leadership of the Bhumjaithai Party, particularly the influential Buriram faction led by Mr. Saksayam Chidchob, former Minister of Transport. During Mr. Piyapong’s tenure at the Department of Highways, he was entrusted with overseeing mega-projects, especially motorways. Even after Mr. Saksayam left the ministry and the Pheu Thai Party took over, Mr. Piyapong retained the trust of Minister Surya Jungrungkit to handle various responsibilities, despite serving as an inspector general at the time, before being appointed the youngest Director-General of the Department of Highways on 1 October 2025.
Nonetheless, the nomination to become the new Permanent Secretary of Transport, succeeding Mr. Chayatham who retires on 30 September, is seen as a promotion to a suitable position for Mr. Piyapong. The Bhumjaithai Party plans to promote Buriram’s influential figure, Mr. Chayut Lohakit, Deputy Director-General of the Department of Highways (Operations), directly aligned with Mr. Newin Chidchob and Mr. Saksayam, to become the new Director-General of the Department of Highways.
Besides Mr. Chayut’s close ties with Buriram’s faction, he is also a native of Songkhla province. Therefore, any reshuffle and transfer must be conducted appropriately and improve upon the current situation. Promoting Mr. Piyapong to Permanent Secretary is thus a suitable course. Once the new Permanent Secretary is officially installed, the Ministry of Transport will appoint a committee to select a new Director-General of the Department of Highways, opening applications to level-9 civil servants, with Mr. Chayut expected to apply for this position.
, Meanwhile, the Ministry of Transport plans to reshuffle senior executives, including appointing or transferring two Deputy Permanent Secretaries and one Inspector General. It is anticipated that the Buriram faction will arrange for Mr. Jirapong Thepphitak, Deputy Permanent Secretary of the Ministry of Transport, to resign from civil service to join the selection process for Director of the Port Authority of Thailand (PAT), with applications closing at the end of August. Alternatively, they may transfer Mr. Jirapong to serve as Director-General of the Marine Department, replacing Mr. Kritphet Chaichuay, the current Director-General, who is expected to resign to apply for the PAT Director position. This move would allow Mr. Kritphet to remain as PAT Director for another three years, as his retirement at the Marine Department would have been only one year away.
Mr. Piyapong Jiwattanakulpaisan, the 35th Director-General of the Department of Highways and the new Permanent Secretary of Transport, is a young executive in the ministry. At only 50 years old, he is the youngest Permanent Secretary in the ministry’s history, with a remaining civil service period of 10 years until his retirement in 2036. He is regarded as a senior official poised to establish foundational leadership and oversee mega transport projects continuously.
His academic background includes engineering and transport studies from top domestic and international institutions: a Bachelor of Engineering (Civil Engineering) from Chulalongkorn University (1997), a Master of Engineering (Transportation Engineering) from the Asian Institute of Technology (AIT), and a Doctor of Philosophy (Transport Studies) from Imperial College London, UK, as a government scholarship recipient.
His career path has steadily advanced through technical, planning, and management roles in expressway projects, marking him as a protégé of the Department of Highways.
Mr. Piyapong is recognized for his outstanding achievements in mega-project management, specializing in driving and accelerating large-scale infrastructure investments, notably key motorway networks such as Bang Pa-in–Nakhon Ratchasima (M6) and Bang Khun Thian–Ban Phaeo (M82). His management approach emphasizes data-driven decision-making, enhancing safety standards at construction sites, and increasing transparency in large joint venture contracts.