The MFP won the May 14 election with 151 seats – 112 constituency and 39 party-list seats. Pita, meanwhile, said that he is ready to become Thailand's 30th prime minister.
“If Pita is proposed as the next prime minister, I will vote against him,” he said.
Earlier, Pita announced its plan to partner with Pheu Thai and four other parties in a move to ensure the junta-appointed Senate does not block their move to form a government.
The alliance, which includes Thai Sang Thai, Prachachart, Thai Liberal and Fair parties, will give the coalition 309 seats. However, this will still be short of the 376 seats needed to ensure Pita gets the top job.
Pita said the five parties are ready to discuss details including policies and a work plan. He added that his party would form a memorandum of understanding with the five parties to ensure transparency.
A coalition with six political parties will be enough to set up a majority government, he said.
As for the lese-majeste law, he said he will raise this issue in Parliament, adding that the law will only be “amended”.
Many pro-democracy protesters are languishing in jail over lese-majeste charges.
Pita said conflict is normal in politics and democracy is the best tool to solve it. However, he said, it may take some time and patience to tackle this issue.