The opposition has called on coalition parties and the Senate to back a motion for a general debate in parliament on the child daycare centre massacre in Nong Bua Lam Phu.
Adisorn Piangket, the spokesman of the opposition leader, said the motion needs the backing of at least one-third of lawmakers in parliament, or 243, to initiate a debate in the next ordinary session.
However, opposition parties have only 210 MPs between them, so they are reaching out to coalition parties and the Senate to support the motion.
Mr Adisorn said the debate would centre on the mass killing in Nong Bua Lam Phu and discuss narcotics suppression, gun control and related issues.
He said several government MPs have shown an interest in backing the motion. The opposition was in the process of gathering signatures from MPs to initiate the motion although it was unclear if it would be able to solicit enough support.
Sukhumpong Ngonkham, a member of Pheu Thai's legal team, said the opposition expected the motion to be initiated under Section 152 of the constitution and it could be submitted to parliament in the middle of next month, assuming it could pull in enough support.
Meanwhile, Chinnaworn Bunyakiat, a government deputy chief whip, said there was no need to hold a general debate as the government was willing to answer specific issues put to it during normal parliamentary sessions.
He insisted the opposition should not make it customary to try and open a general debate or file a no-confidence motion every time parliament reconvenes an ordinary session. It should concentrate on the issues that matter.
However, the government stood ready to answer queries, should the opposition be intent on using the general debate as a tool to discredit it, Mr Chinnaworn said.