A Thai minister once jailed for conspiring to smuggle heroin into Australia is facing censure for lying to the country’s Parliament about revelations of his criminal past.

Government enforcer Thammanat Prompao, who pleaded guilty to a heroin trafficking charge in Sydney in 1993, is among six Thai MPs facing a week-long censure motion.

The Age's front page from September 9 is shown during Wednesday's censure debate against embattled Thai minister Thammanat Prompao, right, in Parliament in Bangkok. Credit:Facebook

The opposition accuses Thammanat of being ineligible to be a cabinet minister because of his criminal record, and says he misled Parliament by lying about the case after the Sydney Morning Herald and Age published stories in September detailing his drug-trafficking conviction.

At the height of the lengthy censure debate, Thammanat attempted to block the admission of Australian court documents which in part formed the basis of the Herald and Age’s reports.