Education Minister Teerakiat Jareonsettasin is scheduled to meet privately with Prime Minister Prayut Chan-o-cha at Government House on Tuesday.
Teerakiat declined to attend the weekly Cabinet meeting earlier that morning, instead staying in his office at the Education Ministry.
Informed sources said he would speak to reporters after his meeting with the premier.
BBC Thai reported that Teerakiat, at a reception at the Thai Embassy in London last Friday, said he would resign if he were found to own luxury wristwatches.
The minister mentioned no names, but the reference was clearly to Deputy Premier and Defence Minister Prawit Wongsuwan, who is under fire for being in possession of at least 25 expensive watches.