Pheu Thai Party's prime ministerial candidate Srettha Thavisin posted a video message on his Facebook account on Friday claiming that whistleblower and former parlour tycoon Chuvit Kamolvisit made allegations of improper business dealings against him because Mr Srettha declined to buy some of his land on Soi Sukhumvit 24 last year worth 2 billion baht.
Mr Srettha is attempting to fend off the corruption allegations ahead of the next round of voting for a new prime minister next week.
Parliament will meet on Tuesday to decide whether to vote for him and end three months of political deadlock since the May 14 general election.
Mr Srettha, a wealthy property mogul, said Sansiri -- the property developer of which he was CEO -- strictly abides by good governance principles and steadfastly observes all legal procedures without seeking to exploit them for self-serving purposes.
He said the company has never faced any such accusations before.
"We are transparent in our work. I come here today to show my innocence to the general public, and to say that my activities were done in accordance with the law," he said.
Mr Srettha denied all of Mr Chuvit's accusations. He said Sansiri buys land and has no obligation to intervene with the interior administration of the seller.
As a purchaser, it does not use nominees and never takes out loans, he said, referring to Mr Chuvit's other claim on Tuesday that the company used four nominees and a 1-billion-baht loan from its subsidiary previously to purchase land in the Thong Lor area of Bangkok.
The 1 billion baht alluded to was the mortgage agreed to and signed by both parties, coupled with the attendant insurance policy, Mr Srettha said.
"I have all the evidence and I insist there was no such loan contract. I am not involved in any illegal activities and neither myself nor the Sansiri employees ever receive any money from corruption," Mr Srettha wrote.
Mr Srettha claimed Mr Chuvit simply has an axe to grind over a property deal last September that never materialised. Sansiri was not able to buy the land as Mr Chuvit's land was legally tied to another company, Raimon Land.
"Since then, I have been threatened by Mr Chuvit's aides via messages demanding that I pay the deposit to buy [Mr Chuvit's land] at the full price.
"[He wanted] me to sign an MoU on the land purchase deal without any conditions after Pheu Thai decided to nominate me as its prime ministerial candidate," Mr Srettha wrote.
He also urged Mr Chuvit to stop distorting information about Pheu Thai's digital wallet policy.
Mr Chuvit posted photos online of one of the alleged nominees to back his claim.