Prime Minister Prayut Chan-o-cha on Wednesday hinted at his concern about the lack of unity ahead of the election, urging all stakeholders to prioritise peace and security.
Gen Prayut, however, stopped short of elaborating on what he was concerned about.
"I don't need to say it all, and I will leave it to you to think what can cause unrest in society," he responded when asked to explain his concern.
When asked whether his concerns have something to do with the possibility of certain parties and groups switching sides after the general election in May, Gen Prayut said that wasn't the case and abruptly changed the subject.
He offered to speak to the press after having lunch with leaders of the armed forces at an event marking the 136th anniversary of the Ministry of Defence.
As he left the ministry, the PM beckoned reporters to get closer to him and conduct the interview.
He cited a literary work by King Rama VI entitled Rai Rak Rai Phon ("Without love, without success") to stress the importance of national unity and peace, which was also adapted into a song.
Gen Prayut said he had warned previously that the absence of peace will cause Thailand to lose many opportunities at the international level.
"I recommend listening to this song by King Vajiravudh [Rama VI] again as many of you appear to have forgotten it," he said.
Previously on Tuesday, Jatuporn Prompan, ex-chairman of the now-dissolved United Front for Democracy against Dictatorship (UDD) and now one of Pheu Thai's most vocal critics, called attention to the possibility of a secret deal between the ruling Palang Pracharath Party (PPRP) and the main opposition Pheu Thai Party.
Under the deal, the parties would form a coalition government and nominate Deputy Prime Minister and PPRP leader Prawit Wongsuwon as the next prime minister after the next poll, according to Mr Jatuporn.
The fact that the wife of a close friend of Gen Prawit has been named candidate No.22 on Pheu Thai's party list prompted Mr Jatuporn to comment about the ties between the parties, and rumoured secret deal between the PPRP and Pheu Thai, which Pheu Thai has repeatedly denied.
