
The merger between the faction and the party will take place tomorrow. All faction MPs are expected to attend the ceremony witnessed by leader Newin Chidchob.
"The revamped party will welcome everyone interested to join its political activities," Supachai said, hinting at a bid to build a powerful party for Isaan MPs and those from the lower North.
The party will comprise MPs backed by Newin, supporters of faction leader Somsak Thepsuthin from the disbanded Matchima Thipataya Party, and those under faction leader Sora-at Klinpratoom.
Like Newin, Sora-at is a former ally of Pheu Thai but has switched loyalty to the Democrat-led coalition.
In his dual capacity as government deputy spokesman, Supachai said the by-election outcome has boosted the coalition majority and strengthened the government.
"The votes cast in favour of the coalition have rebutted the allegation the government might have grabbed power by illegitimate means," he said in reference to the switching of allegiance from Pheu Thai to Democrat parties.
He said the balloting outcome should remind opponents to respect the voter's judgement and to stop questioning the government's legitimacy.
He said he believed the defeat of Pheu Thai in a number of constituencies could be blamed on a number of factors, including public disapproval of unruly protesting by red-shirt crowds.
He ruled out speculation that Phue Thai's poor performance at the polls resulted from the declining popularity of ex-premier Thaksin Shinawatra.
"I think voters have sent a clear signal they want politicians to work within the parliamentary system instead of straying to fight through street protests," he said.
He added the by-election vote revealed Phue Thai no longer had a dominating influence in the Northeast, providing proof his faction could survive after parting ways with Thaksin.