
Nipit, who represents Phatthalung, complained about what he called "increasing influence" on the Democrat Party by business.
"The problem and peril for today is that business groups have become influential in the party. They've become more powerful than MPs and party executives, which is dangerous in setting the party's direction," he said.
The MP was referring to the likely appointment of Virachai Virameteekul, an executive with the Charoen Pokphand Group, as a Prime Minister's Office minister under the Democrat quota.
Nipit said he had written an open letter to Virachai asking him to become a Democrat Party member in order to prove his sincerity.
He said he had also asked Virachai to make it clear which business group he represented.
The MP noted that Virachai had worked in the Thaksin Shinawatra and Surayud Chulanont administrations.
He also questioned Virachai's loyalty to the party when it was in opposition.
Nipit told reporters he was unhappy about the matter because he believed he was qualified for a Cabinet post. As well, he said Chuan Leekpai, the party's chief adviser and former leader, had told Nipit's electorate in Phatthalung that he would support his becoming a Cabinet member.
However, Nipit ruled out any possibility of leaving the party.