Prime Minister Samak Sundaravej on Sunday hit out at an "invisible hand" he says continues to pull the strings behind attempts to rock the government and the People Power party.
"Although the government has been formed, this (invisible hand) never gives up," he said in his weekly TV address.
"The leader should watch out."
He said he would disclose who is the invisible hand, and take action against anyone trying to undermine his administration.
After the programme, he told reporters he was gathering evidence to take legal action against those trying to undermine the administration and his party, including attempts to intimidate people to put an end to the PPP.
Mr Samak said opponents were using a three-pronged approach to try to rock the new government:
False reports he would abolish the Bank of Thailand's 30 per cent capital control measure
Erroneous stories that he was trying to place former executive members of the disbanded Thai Rak Thai party on the boards of state enterprises
Poll fraud allegations against House Speaker Yongyuth Tiyapairat.
Mr Samak accused the invisible hand of being behind all three issues, which have received wide media coverage.
"There is something fishy in news reporting" because of vague news sources, he added.
He denied interference in the Finance Ministry and the policy on capital control measures. He defended Finance Minister and PPP secretary-general Surapong Suebwonglee, who was forced to comment on the former TRT members banned from politics for five years.
The central issue, however, was the result of the investigation into Mr Yongyuth, a PPP deputy leader.
The prime minister blasted those who leaked the results of an inquiry into Mr Yongyuth's case undertaken by an Election Commission panel.
Mr Samak attached those who leaked the results to the media, saying it was a "dirty trick" aimed at destroying the government and the PPP.
The EC found him guilty of bribing local officials in exchange for votes in the Dec 23 general election. Mr Yongyuth will probably be forced to step aside from the House speaker's chair if the EC agrees with the investigation.
He could be banned from politics for five years if found guilty by the Supreme Court. If he is convicted, the party could be disbanded if there is evidence that it was aware of Mr Yongyuth's illegal actions but did nothing to stop them, because he was deputy leader of the party at the time of the alleged vote buying.