The so-called Group of 16, which is made up of MPs from micro-parties and several members of the Palang Pracharath Party (PPRP), are divided on whether or not they will support Prime Minister Prayut Chan-o-cha in the upcoming no-confidence debate against the government.
Khathathep Techadejruangkul, the group's secretary, said that the group has been monitoring the government's performance and found that it has failed to address the economic problems which have blighted the nation.
"People are still experiencing economic hardship and struggling to make ends meet," he said.
In light of this, the group's key figures have decided that the group will vote against the prime minister, said Mr Khathathep, who is the leader of the Pheu Chart Thai Party.
However, he admitted that members of the group are still divided on whether to part ways with the coalition.
Some members are insisting on joining the opposition while others want to hear the prime minister and other cabinet ministers explain themselves in the debate before deciding whether to vote against them, he said.
"Some members argued that voting against [the censure targets] does not necessarily mean defecting from the coalition," he said.
However, Peerawit Ruengluedollapak, a list MP and leader of the Thai Rak Tham Party, on Thursday said that the group will only vote for Gen Prayut, Deputy Prime Minister and PPRP leader Prawit Wongsuwon, and Labour Minister Suchart Chomklin.
Mr Peerawit also said that it is still not known if the group would vote in the same way as the Setthakij Thai Party led by Capt Thamanat Prompow. The group will meet Gen Prawit on Sunday to discuss the issue, he said.
He said despite Setthakij Thai withdrawing from the coalition, there is no need for the Group of 16 to do so.
"We don't need to do the same as Capt Thamanat did," Mr Peerawit said.
Setthakij Thai, with 16 MPs under its wing, has turned up the heat on the government after Capt Thamanat on Tuesday formally pulled out of the coalition and vowed to vote against Gen Prayut and 10 other cabinet ministers.
Capt Thamanat on Thursday described the party's defeat in the by-election in Lampang's Constituency 4 on Sunday as "a lesson from the people".
"It shows the government's popularity is waning. It also taught me that I should not be overly confident,'' he said.
He also said he will meet Gen Prawit on Sunday to bid him farewell. "I still respect him despite our withdrawal from the government,'' he said.
He has made it clear he will not support Gen Prayut, but he will vote for Gen Prawit in the censure motion.
Capt Thamanat was seen as Gen Prawit's right-hand man when he served as the PPRP's secretary-general.