Noppadon Pattama made the denial after Pefot co-leaders AM Watchara Lithakanee and Thaikorn Polsuwan posted their allegation on their Facebook page on Wednesday.
They also said the ex-premier met politicians from Thailand to make political plans and that his ex-wife Khunying Potjaman na Pombejra went there to meet him and had an argument with his younger sister Yaowapa Wongsawat.
Mr Noppadon denied all allegations, calling them total lies.
He said Thaksin actually left Hong Kong to head for Dubai, stopping in Myanmar only to make merit, which was a normal act just like other Thai Buddhists. There had been no political talks with local authorities.
Khunying Potjaman did not travel to Myanmar, he said, therefore there was no argument between her and Mrs Yaowapa.