(Bloomberg) -- Thai prime minister candidate Srettha Thavisin filed a defamation suit against a whistleblower for alleging he had colluded in evading tax in a land deal with a property company he ran previously.   

The lawsuit, filed by Srettha’s lawyer Winyat Chatmontree in a Bangkok court, seeks 500 million baht ($14 million) in damages from businessman-turned-whistleblower Chuvit Kamolvisit. Srettha was accused of helping a group of people evade tax in 2019 when they sold a plot of land to real estate developer Sansiri Pcl, where he held positions of chief executive and director at the time. 

Chuvit’s accusations, which came a day before Srettha was due to be nominated by Pheu Thai Party for prime minister in a now-suspended parliament vote, were politically motivated to hurt Srettha’s candidacy, according to Winyat.

“Chuvit deliberately left out facts and misled people, with a hidden agenda to hurt the plaintiff,” Winyat told reporters. “The accusations against Srettha were made for political gains, to make the people and lawmakers believe that he had violated the law and breached ethics.” 

Chuvit said he wasn’t worried about the lawsuit, and he was entitled to “honest criticism” of a prime minister candidate.

The allegations add to the hurdles faced by Pheu Thai Party, which is canvassing support among the conservative political parties and pro-royalist Senate to form Thailand’s next government. A near three-month delay in government formation since the May election has kept investors on edge with foreign funds pulling out a net $3.7 billion from the nation’s stocks this year. 

READ: Thailand’s Wait for a Premier Gets Longer, Rattling Markets

To seal the prime minister’s post for Srettha, Pheu Thai — linked to former prime minister Thaksin Shinawatra — needs the backing of the majority of the 750 lawmakers in a joint sitting of the the lower house and the military-appointed Senate. 

Pheu Thai is in talks to form a new alliance after breaking away from a pro-democracy coalition of eight parties led Move Forward Party. Pita Limjaroenrat, the leader of the now-disbanded bloc, was twice thwarted by conservative lawmakers opposed to his party’s reformist platforms.

Parliament has suspended the prime minister selection process pending further clarity from the Constitutional Court, which last week deferred making a decision about Pita’s re-nomination petition. With the political stalemate continuing, Thaksin also delayed his plan to return to Thailand this week, signaling Pheu Thai is far from reaching a deal to form a government. 

READ: Thailand’s Thaksin Delays Plan to Return From 15-Year Exile 

Last week, Sansiri also denied Chuvit’s allegations. The land purchases were legitimate and in accordance with good corporate governance, and nothing illegal was done to help the sellers, Sansiri said in a statement. The developers shares fell about 10% last week. 

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