Deputy PM and Finance Minister Pichai Chunhavajira downplayed criticism of him in a resignation letter written by his former deputy Krisada Chinavicharana.
Mr Krisada wrote in his letter that the main reasons why he quit as deputy finance minister were that he and Mr Pichai had a different work philosophy and that Mr Pichai failed to treat him with respect when they worked together.
"That's understandable," said Mr Pichai on Tuesday when asked about the reasons as outlined in Mr Krisada's letter written on May 8 and published by the media.
"There actually are always reasons [like these] when it comes to working [together], but I simply can't go into detail now," he said.
Mr Krisada also stated in his letter that he had a proven track record of success in pushing to implement important missions, which he was assigned by Prime Minister Srettha Thavisin, who was also the former finance minister.
These tasks included directing government efforts to ease problems associated with high levels of household debt, supporting small- and medium-sized enterprises to cope better with financial challenges and accelerating the disbursement of the 2024 government budget.
As a retired finance ministry official, Mr Krisada said he always ensured the government's spending was strictly in line with financial and fiscal discipline regulations when serving as a deputy finance minister.
The media also published Mr Krisada's May 10 letter that indicated his intention to resign as a member of the United Thai Nation (UTN) Party.
UTN leader Pirapan Salirathavibhaga, meanwhile, said he had already talked to Mr Krisada on the phone, and the latter affirmed his decisions.
Mr Pirapan declined to comment on the reasons cited by Mr Krisada in his resignation letter, which pointed an accusing finger at Mr Pichai, saying that was a rather personal matter.
He said the UTN would nominate someone else who would be suitable to replace Mr Krisada as the new deputy finance minister.
Deputy Finance Minister Paopoom Rojanasakul said he had learnt about Mr Krisada's resignation letter solely from media reports.
If the reported statement is confirmed, Mr Paopoom said he would respect Mr Krisada's decision.
Mr Paopoom said he has known Mr Krisada for 10 years since they worked together at the Fiscal Policy Office.
Krisada Chinavicharana