The Polish center-right "Law and Justice" party (PiS) split after its leader Jarosław Kaczyński expelled former Prime Minister Mateusz Morawiecki amid a dispute over the party's future direction, DPA reported, BTA reported.
While Kaczyński described the split as a voluntary resignation by Morawiecki and a group of MPs supporting him, refusing to sign an oath of loyalty to the party, Morawiecki and political observers called the leader's actions a "forced removal".
Forty members of parliament are also leaving, Morawiecki said, who has not yet indicated whether he intends to create his own party.
At the center of the conflict is the future direction of the former ruling party, which was in power from 2015 to 2023. During its rule, PiS transformed Poland according to its own vision, which has plunged it into a prolonged conflict with the EU, DPA noted.
In March Kaczynski nominated hardliner Przemysław Czarnek for the post of prime minister in next year's parliamentary elections. He said his goal was to make PiS more attractive to far-right voters.
The economically liberal former banker Morawiecki, 58, who was prime minister from 2017 to 2023, felt ignored by Czarnek's nomination, the DPA reported.
He responded by creating the "Development Plus" group, which included his moderate colleagues, and demanded that PiS "return to a broad coalition with Poland's right-wing and center-right parties."
Kaczynski, in turn, gave an ultimatum for the group to dissolve and for all its members to sign a declaration of loyalty. Morawiecki let the ultimatum expire. "We cannot afford to be forced to sign loyalty declarations," he said after leaving the party.
On Tuesday, party authorities are expected to formally approve the resignation of Morawiecki and "30 of his supporters," Kaczynski announced. With 186 deputies, PiS was previously the largest party in the Polish parliament.