Thai Prime Minister Prayuth Chan-ocha said on Monday he had not ordered his military-dominated legislature to vote against ousted former Prime Minister Yingluck Shinawatra when her impeachment hearing concludes this week.
Yingluck's supporters and former members of her cabinet say the National Legislative Assembly (NLA) will vote against the former premier in a bid to try to end the political influence of her powerful family, including her brother, former Prime Minister Thaksin Shinawatra.
Prayuth denied those allegations.
"I have never sent any signal. Never. There has never been an order," Prayuth told reporters in Bangkok.
All 220 members of the NLA were hand-picked by the junta, known as the National Council for Peace and Order. Around 100 of them are former or currently-serving military officers.
A decision to ban Yingluck from politics would require three-fifths of the vote.
The hearings, which began on Jan. 9, concern Yingluck's role in a controversial rice subsidy scheme. The NLA will vote on Jan. 23 whether it finds Yingluck guilty of negligence over the scheme, a flagship policy of her administration.
If found guilty, Yingluck would be banned from political office for five years.
Yingluck, Thailand's first female prime minister, came to power in a landslide election in 2011, backed by farmers mostly in the north and northeast of the country.
She was removed from office in May, after a court found her guilty of abuse of power, days before the military staged a coup after months of street demonstrations in Bangkok aimed at ousting her government.
A day after she was removed, Thailand's National Anti-Corruption Commision found her guilty of mishandling the rice scheme. The scheme paid farmers well above market rates for their crops and caused losses of more than $15 billion to the state.
Thailand has been convulsed by bouts of political turbulence ever since Thaksin was removed in a previous putsch in 2006. It remains divided between supporters of Yingluck and Thaksin and the royalist-military establishment which sees Thaksin, a populist former telecommunications tycoon, as a threat.