The Thai election winner, Pita Limjaroenrat, has been temporarily suspended as a member of Parliament by the Constitutional Court in Bangkok on Wednesday.
The court granted a corresponding request by the Election Commission, according to a statement released.
The decision became known while parliament was debating the upcoming second vote on Pita as the future head of government.
Pita is being investigated over allegations that he owned shares in a media company during his run for office.
This is illegal in Thailand.
According to him, the media company in question, whose shares came from his father’s estate, has been defunct for a long time.
Pita’s progressive Move Forward Party were clear winners in the parliamentary election in May.
In spite of his suspension as a member of parliament, he could still be elected Prime Minister, according to media reports.
But for him to must secure majority back from the lower house of parliament, made up of elected MPs, and from the military-dominated senate.
For a candidate not affiliated with the Army, campaigning on a platform of reforms that would separate the military from politics, that looks unlikely.
Pita had already lost a first vote in parliament last week.
dpa/NAN