Chaiyos Jiramethakorn, acting Puea Pandin party spokesman, held a press conference, announcing that 20 of its 27 MPs agree to support Democrat party in forming a new government.
The statement came amid a suggestion by Pracharaj leader Sanoh Thienthong that he backs Puea Pandin leader Pracha Promnok as new prime minister.
He said that most of the party members would back Pol Gen Pracha in the next election, because he already announced that he would not take the post.
Mr Chaiyos added that the seven remaining MPs have not made up their mind who they would back.