The Defence Ministry will comply with a court order to explain its draft-dodging case against Democrat Leader Abhisit Vejjajiva, Defence Minister Sukumpol Suwanatat said on Saturday.
The ministry would submit its statement within 30 days as the Administrative Court requested, he said, even though it has evidence to support the decision to strip Mr Abhisit of his military rank.
Loss of military rank for an alleged transgression that took place 25 years ago could put Mr Abhisit at risk of losing his status as an MP as well.
ACM Sukumpol said he would hold talks on Monday with the Judge Advocate General’s Department on future procedure in Mr Abhisit’s case.
The minister insisted he was not persecuting the opposition leader as alleged, because there was no reason to do so.
If Mr Abhisit had not done anything wrong, the Defence Ministry would have had no justification to order his retroactive dismissal him from military service, he added.
"As a former prime minister, isn't he ashamed for draft-dodging and using fake documents to become a lecturer at Chulachomklao Royal Military Academy?" the minister asked rhetorically.
"He had repeatedly said that he opposed corruption but he did this thing himself. Is this Thailand?
"Talking about this case must be based on actual fact," said ACM Sukumpol.
The Administrative Court on Friday accepted Mr Abhisit's petition against ACM Sukumpol's order stripping him of his military rank.
ACM Sukumpol and other Pheu Thai Party members have denied claims that they hastily resurrected a 25-year-old case in an attempt to sideline Mr Abhisit ahead of last week's parliamentary censure debate.
The minister signed a Nov 8 order retroactively dismissing Mr Abhisit from the Army Reserve, revoking his military rank and recalling his salary.
He said Mr Abhisit had used fake documents to become a lecturer at Chulachomklao Royal Military Academy, a job that exempted him from the army in 1987.
The Democrat leader denied the allegations and assigned party lawyer Bandit Siriphan to file a petition against ACM Sukumpol's order on Nov 12.
The court deferred its decision on Nov 20, saying the case required further judicial review. It then asked both sides to hand in their documents six days later before holding a hearing on Friday.
The Election Commission (EC), mewanhile, agreed last week to set up a panel to investigate whether Mr Abhisit is qualified to serve as an MP.
Former senator Ruangkrai Leekijwattana had asked the EC to rule on Mr Abhisit's qualifications after ACM Sukumpol's order.
If the EC rules against Mr Abhisit, the case will be sent to the House speaker who is authorised to seek a final ruling from the Constitution Court.