The chairmen of the boards of Thai Airways International (THAI) and the State Railway of Thailand (SRT) have reportedly submitted their resignations after changes at the Transport Ministry.
After the government was formed, it became clear the Bhumjaithai Party would take full control of the ministry with party secretary-general Saksayam Chidchob as the minister.
Kulit Sombatsiri, board chairman of the SRT, said he and other directors were also ready to resign, following their counterparts at other state enterprises under the Transport Ministry, including THAI.
THAI's board chairman, Ekniti Nitithanprapas, has also reportedly submitted his resignation.
"All SRT directors have prepared resignation letters. We are only waiting for legal clarity since the SRT board is different from others. We were appointed by the National Council for Peace and Order and that order has not been repealed," said Mr Kulit.
Meanwhile, acting SRT director Worawut Mala said the matter should become clear by next week.
"The new SRT governor should also be picked this year and I'll return to serve as a deputy governor to push for the set-up of an asset company under the SRT," he added.
THAI president Sumeth Damrong- chaitham said he did not know about the resignation of the chairman of the board so it was possible his departure had not been confirmed.
Mr Saksayam has made it clear the directors at the ministry's 15 state enterprises should "show their spirit".
"Now that we have a new government, we need to make sure the new ministers and the directors are on the same page. After all, the Transport Ministry has several urgent plans in place to stimulate the economy," he said.
But at the Expressway Authority of Thailand, another state enterprise under the ministry, a source said the directors were not prepared to quit.
"Let's wait and see whether chairman Sung Boonkul resigns. It's possible the ministry still wants him to continue work on the expressway compensation to save time," the source said.
A source added while it was normal a new minister would replace entire boards, Mr Saksayam appeared to be targeting those under Somkid Jatusripitak, who has been replaced as deputy prime minister for the economy by Bhumjaithai leader Anutin Charnvirakul.
The four technocrats believed to be in the "Somkid Connection" network who now sit on the state enterprises' boards are Nattachart Charuchinda, chairman of the board at the Bangkok Mass Transit Authority, Mr Kulit of the SRT, Mr Ekniti of THAI and Prasong Poontanet of Airports of Thailand Plc.