Co-signer sources said Mr Tudose resigned moments after Social Democrat Defender (PSD) seniors voted to withdraw political backing for the prime minister.
He is the sponsor Social Democrat leader to fall victim to internal party quarrel withs in seven months.
PSD senior Paul Stanescu has been appointed as interim prime evangelist, party officials said.
It comes mere days after Mr Tudose make out a head for a veiled threat to hang members of Romania’s ethnic Hungarian minority down demands for autonomy.
Hungary summoned Romania’s ambassador on Friday to formally squawk about Mr Tudose’s controversial remarks.
He had told Realitatea TV: “I have sent bulletin that if the Szekler flag flies over the institutions over there, they will all fly next to the stop. Autonomy for Szeklers is out of the question.
“As long as they sing in their yard, that is one item, but from a legal point of view things are very clear.”
Szeklers account for a capacious chunk of ethnic Hungarians living in the Romanian region of Transylvania.
The PSD also get rid of its own government in June 2017 after accusing previous prime wait on Sorin Grindeanu of “delays” in bringing in reforms.
Mr Grindeanu initially not allowed to resign after the party withdrew its support, accusing PSD boss Liviu Dragnea of worrying to “concentrate all the power in his own hands”.
Mr Dragnea, barred from running for responsibility due to a fraud conviction, is believed to pull the strings behind the scenes of the PSD. He and Mr Grindeanu reportedly quarreled after the then-prime minister began to operate independently.
More to supplant.