Two MPs attacked Pramuan, author of the best-seller “Royal Powers”, as he was giving a speech at Thammasat University.

Parts of the book touch on the impasse over the auditor-general nomination involving Khunying Jaruvan Maintaka.

Thai Rak Thai deputy spokesman Chatuporn Prompan cited Pramuan’s disappointment at losing his Cabinet post as his motivation to oust the government.

He said Pramuan should understand that he lost his deputy interior minister post because he floated a proposal to cancel local leadership elections, a move which was labelled a big step back for democracy.

“Since he lost his ministerial post, he has held a prejudice against the PM [Thaksin Shinawatra] and has joined hands with others who are trying to remove the government,’’ he said.

Chatuporn called Pramuan ungrateful, saying he had “set fire to his own party”. “Pramuan has challenged the party to expel him but if he is not happy, he should quit,” he said.

Suwat Wansirikul, head of Thai Rak Thai’s Bangkok MPs, agreed the party should take action against Pramuan.

“As a party MP, he should have political etiquette and respect the party and the party leader,’’ he said.

“He challenged the party to sack him because he does not want to lose his MP status. One day his wish will come true.’’