Tunisian Prime Minister Elyes Fakhfakh resigned on Wednesday, according to two official sources who did not want to be named, after a row with the Ennahda party.
Fakhfakh, who is under investigation over allegations of conflict of interest, has had strained relations with Ennahda, the biggest party in parliament, since October legislative elections.
Ennahda had earlier Wednesday tabled a no-confidence motion against Fakhfakh, who took office in February after winning approval from lawmakers following four months of deadlock.
Ennahda came top in the October polls but fell far short of a majority and eventually agreed to join a coalition government.
The party initially nominated an independent for premier but he failed to win the support of parliament, leading President Kais Saied to name former finance minister Fakhfakh for the post.
Fakhfakh is under investigation over alleged failure to hand over control of shares he owns in private companies that have won public contracts.