The opposition is planning to pursue legal action against Prime Minister Prayut Chan-o-cha and some cabinet ministers in connection with the no-confidence debate last week, said chief opposition whip Sutin Klungsang.
All six opposition parties have decided to seek legal action against Gen Prayut and some of the ministers targeted in the censure motion.
Gen Prayut and five ministers were named in the motion and survived the censure. The ministers were Anutin Charnvirakul, deputy prime minister and public health minister; Saksayam Chidchob, transport minister; Chalermchai Sri-on, agriculture and cooperatives minister; Suchart Chomklin, labour minister; and Chaiwut Thanakamanusorn, digital economy and society minister.
On Wednesday, Mr Sutin said the opposition was satisfied with its MPs' performance in the debate.
It had expected the premier and the ministers to pull through the motion as no government in the past has been defeated in a no-confidence vote.
However, the debate was fraught with irregularities, including how the government managed to muster confidence votes from its MPs.
During the debate, Wisarn Techathirawat, a Pheu Thai MP for Chiang Rai, accused Gen Prayut of paying five million baht to some MPs in exchange for votes of support. The government has since said it will file criminal action against Mr Wisarn over the accusation.
Mr Sutin said the prime minister and his ministers failed to provide clear answers to many censure queries, including the purchasing price of the Sinovac vaccine and details of the purchase deal.
The procurement of antigen test kits also raised questions, to which the government did not adequately respond, he added.
He said the opposition has solid evidence in the five-million-baht payoff, adding a complaint will be lodged with the National Anti-Corruption Commission and the Constitutional Court.