The probe into the luxury watches allegedly owned by Deputy Prime Minister Prawit Wongsuwon is still ongoing and is not being stalled, the national anti-graft body said Thursday.
However, National Anti-Corruption Commission (NACC) secretary-general Worawit Sookboon said it is unlikely the commission will meet this month's deadline to wrap up the case.
The investigation requires another two to three months, he said.
His remarks prompted Mana Nimitmongkol, secretary-general of the Anti-Corruption Organisation of Thailand, to urge the NACC to keep the public regularly informed on the probe's progress for the sake of transparency.
He refused to comment when asked if he thought the NACC was stalling.
Mr Worawit said the speed of the probe depends on how quickly luxury watch dealers respond to NACC requests for information about the 22 watches seen worn by Gen Prawit, and which sparked speculation over Gen Prawit's wealth.
Although it is not complicated verifying the 22 watches' owners via the serial numbers, it takes time repeating the same process for each watch, Mr Worawit said.
"The questioning of witnesses, including the children of Pattawat Suksriwong, the late close friend of Gen Prawit, is completed," said Mr Worawit.