Thailand's parliament has decided the leader of the Move Forward Party, Pita Limjaroenrat, cannot be re-nominated to be a prime ministerial candidate.

Pita failed to secure a majority in last week's vote. He was expected to run in the second round of voting on Wednesday.

The parliament passed a motion before the poll. The motion indicated Pita was ineligible for the second round of voting. It was submitted by conservative lawmakers. They said a re-nomination would contravene a parliamentary regulation.

That means Pita cannot be the MFP's candidate. The eight opposition parties will now nominate a candidate from the second largest Pheu Thai Party.