The education minister has accused a Future Forward Party (FFP) MP in Chachoengsao of exploiting school visits to turn students against mandatory military conscription.
Ending mandatory conscription is a key policy of the FFP.
"The Education Ministry already supports students learning about democracy in various extracurricular activities including the student council. So, it's not right for a particular politician or party to take advantage of them and lure them into believing any specific political propaganda," wrote Education Minister Nataphol Teepsuwan on his Facebook page.
"They are instigating hatred [against the military] among the young, which is an evil thing to do. Every MP should instead contribute to promoting education, not exploiting the young as a political tool," said Mr Nataphol, apparently referring to the FFP and its MP for Chachoengsao, Chirat Thongsuwan.
Mr Chirat, whose speech about the FFP's campaign to end military conscription at a school in Chachongsao recently sparked controversy, meanwhile accused the government of looking down on the young and pressuring school executives to act against what he described as his effort to educate students about their rights.
"I condemn any attempt to make this [the anti-military conscription campaign at schools] the wrong thing to do," he said.
He also questioned why the military was allowed to disseminate its own one-sided information through its territorial defence training programme.
"The military must make the conscription matter open to debate," Mr Chirat said.
"The young have every right to information about this as it is they who are affected, not the military, the government or any cabinet minister," he said.
As for his recent visit to Phai Kaew Witthaya in Plaeng Yao district on Dec 2, which sparked strong criticism on social media, he insisted he had been given permission by the school's executives to speak to the students.
The controversial speech was delivered in the presence of the school's director and teachers who assured him that what he had said to their students was unlikely to cause any harm, according to Mr Chirat.
He said he asked the students to raise their hands if they didn't want to become a soldier and everyone did which led him to conclude that no one actually wants military conscription.
He said this overwhelming response had only encouraged him to scale up his campaign and visit more schools.