The ruling Palang Pracharath Party (PPRP) has declared it will nominate its leader Gen Prawit Wongsuwon as its lone prime ministerial candidate, according to party secretary-general Santi Promphat.
The party is also unperturbed in going head-to-head with the United Thai Nation (UTN) Party, which unveiled Prime Minister Gen Prayut Chan-o-cha as a member on Monday, Mr Santi said.
On Tuesday, Gen Prawit, also a deputy prime minister, reaffirmed that his fraternal bond with Gen Prayut remains as strong as ever despite the latter breaking away from the PPRP to join the UTN.
He said that he and Gen Prayut talked to each other all day on Tuesday, adding that political issues were not part of the conversation.
"It's still the same between us. Nothing has changed," Gen Prawit said.
This sentiment about the two men's bond was echoed by PM's Office Minister Thanakorn Wangboonkongchana.
Mr Santi said the PPRP would meet in two to four days when it will officially name Gen Prawit as the party's only prime ministerial candidate.
The sole candidacy would work to the party's success at the next poll tentatively scheduled for May 7, he said.
"Gen Prawit is the right choice to be the next prime minister, given his military background and knowledge of economics," said Mr Santi, also deputy finance minister.
"There's also another side to him that not many people know about, and that is his ability to put the right people in the right jobs, which has been the reason several state projects such as water and land management have been a success," he said.
The party is united, Mr Santi said, adding that although the PPRP does not see Gen Prayut as a rival in the election, the ruling party was ready to give the UTN a run for its money.
The PPRP was unperturbed by the UTN's presence on the political scene, Mr Santi said while admitting that in some constituencies, the two parties might compete strongly against each other.
"If one party stepped away [from the constituencies] for the other, voters would have fewer choices of candidates to consider, which would be unfair," he said.
"The PPRP will pull out all the stops to fight the election in every constituency," he said.
Meanwhile, Chanapa Sinthuprai, deputy spokeswoman of the main opposition Pheu Thai Party, said the showcasing of Gen Prayut's membership on Monday was just an attention-grabbing tactic.
Several UTN members were former protest leaders blamed for creating the political situation that led to the military coup in 2014, Ms Chanapa said.
Also on Tuesday, Veerakorn Kamprakob said he had resigned as the PPRP MP for Nakhon Sawan and defected to the Bhumjaithai Party.
Mr Veerakorn said he quit the ruling party partly because Gen Prawit was not always accessible to party members and that the PPRP's popularity was waning.