The standoff comes after the party's leadership ordered members to quit any politically active associations or face expulsion.
Party spokesman Rafał Bochenek said on Thursday that the leadership's decision was final and that party members must choose between PiS and "outside organizations engaged in political activity."
"You either want to belong to one organization or the other," Bochenek wrote on X.
The party's leadership announced the decision on Wednesday, requiring members to resign from associations including Morawiecki's Development Plus and Poland First, founded by senior PiS lawmaker Jacek Sasin.
Bochenek said members who fail to comply by July 23 will face expulsion proceedings.
He argued that Development Plus pursues political objectives that conflict with PiS and accused the association of undermining the party's structures, using PiS resources to build a separate organization and fueling internal divisions.
"Despite attempts to claim otherwise, it must be said clearly: the Development Plus association does not strengthen but harms the unity of the Polish right," Bochenek said.
He also said the decision was driven in part by legal and financial concerns, arguing that Polish law prohibits political parties from financing other entities or receiving funding from outside organizations.
Bochenek warned that any overlap between PiS and politically active associations could expose the party to further financial penalties.
PiS lost part of its state funding after Poland's National Electoral Commission (PKW) rejected the party's financial report for the 2023 parliamentary election, citing campaign spending irregularities.
The finance ministry subsequently reduced the party's public subsidy, although PiS has challenged the decision in court.
Morawiecki, who served as prime minister from 2017 to 2023, responded by insisting he intended to remain in PiS while continuing to develop his association.
"My declaration is clear: I want to remain in PiS, I want to step up Development Plus. I want an ambitious Poland to win. All of this is possible only together," he wrote on X.
He also criticized what he described as attempts to deepen divisions within the party.
"At a time when Tusk's government is facing its biggest crisis, numerous scandals, a healthcare system in collapse and conflicts within the governing coalition, creating internal divisions in our party by a narrow group of intriguers is the last thing we need," Morawiecki wrote.
Sasin, by contrast, accepted the party leadership's decision and announced on Wednesday that his Poland First association would cease operations.
Morawiecki launched Development Plus in April, presenting it as a platform for promoting policy ideas. However, some senior PiS figures have viewed it as an attempt to establish an independent power base within the party.
PiS, led by veteran politician Jarosław Kaczyński, has been in opposition since losing power to Prime Minister Donald Tusk's coalition in the 2023 parliamentary election.
Internal jockeying over the party's future leadership has intensified as it prepares for the next parliamentary election, scheduled for autumn 2027.
Mateusz Morawiecki and Jarosław Kaczyński. Photos: Agnieszka Bielecka/Tomasz Gzell/PAP
In April, Kaczyński and Morawiecki said they had reached an agreement to defuse tensions over Development Plus after seven hours of late-night talks.
At a joint news conference, Kaczyński said the association, which includes several dozen PiS lawmakers and members of the European Parliament, would operate within the party's structures rather than as an independent political center.
(gs)
Source: IAR, PAP/PAP