Prime Minister Prayut Chan-o-cha hit back at the Pheu Thai Party Monday, after it called on the National Council for Peace and Order (NCPO) and the government to set up a panel to investigate the purchase of the fake GT200 bomb detectors.
He indicated it is the government which is the damaged party and the notion of any state agency being subject to an inquiry may not be reasonable.
"What did the court say? The ruling is against the seller and the manufacturer, right? The court ordered compensation for the buyers, didn't they?" he said, citing a British court's verdict on the matter.
The prime minister also said the GT200 units have not been put to use after their effectiveness was questioned.
On Saturday, Pheu Thai acting deputy spokesman Anusorn Iamsa-ard suggested the NCPO and the government set up a panel to investigate the purchase of the bomb detectors.
He said the investigation should examine how many government agencies had deployed the devices and whether military officers in the current government were involved with the procurement.
Also, it should be checked which state agencies acquired the overpriced detectors, each costing several hundred thousand of baht, which caused massive damage to the country, according to Mr Anusorn.
He added it was puzzling why state agencies with scientific experts had no knowledge the GT200 devices were bogus.
Gen Prayut said Monday Thailand will seek compensation if it is possible. However, the issue has not yet been determined.
The GT200 bogus bomb detectors came back into the spotlight last week after a UK court ordered compensation be paid to affected countries from the forfeited assets of James McCormick, who is serving a 10-year jail term for selling the dud devices.
The British court ordered some of that money be used to compensate nations around the world that bought the devices, including Bahrain, Lebanon, Niger and Georgia. Iraq is due to receive £2.3m (115 million baht) in compensation.
A range of Thai agencies from the armed forces and police to customs and provincial authorities spent nearly 1.4 billion baht on 1,358 detection devices between 2006 and 2010.
The army alone purchased more than 700 units, most of which were used in the restive deep South.
According to Isra News Agency, at least seven security-related agencies signed a total of 19 contracts during 2007-2010 to procure GT200 units.
Critics say the failure of the devices to do as promised has caused deaths and injuries, while false alarms sounded by the detectors led security officers to put innocent people in jail on suspicion of planting bombs.
Deputy Prime Minister Prawit Wongsuwon came out to defend the army's procurement of the bomb detectors, saying the purchase scheme was transparent and in line with the regulations.
His remark followed a plan by the Office of Auditor-General to look into the purchases.
"The auditor will investigate if there was any graft involved [in the acquisition of the detectors]. But I assure the purchases were made in line with regulations," he said.
He said Thai authorities will determine what can be done after the British court's compensation order.
Auditor-General Pisit Leelavachiropas said he has instructed authorities to probe the purchases of the bogus devices and determine if any irregularities were at play.
He described the issue as a case of national fraud and said the Thai distributors will face criminal investigations if the findings indicate they were part of the scam.