ATHENS, Greece (AP) — Greece’s main left-wing opposition party, Syriza, suffered a damaging setback Thursday when nine lawmakers quit the party in protest against its newly elected leadership.

Miami-based businessman Stefanos Kasselakis, 35, stunned party veterans when he won the leadership in late September in a primary-style contest. But he has failed so far to halt the party’s decline in popularity in the wake of a crushing general election defeat in June.

Syriza has since dropped to third place behind Socialist opponents in opinion polls, boosting the dominance of Prime Minister Kyriakos Mitsotakis’ conservative government.

On Thursday, Effie Achtsioglou, a former Syriza labor minister, led the walkout as nine lawmakers declared themselves independent.

They joined the former finance minister Euclid Tsakalotos and another colleague who quit on Nov. 11 – reducing the number of seats held by Syriza in the election from 47 to 36 in the 300-member parliament.

Critics of the new leader have described him as intolerant of dissent and unable to reach a policy consensus in the historically fractured party.

Under the charismatic former prime minister Alexis Tsipras, Syriza’s was transformed from a small political organization to a governing party during a major financial crisis in the previous decade that brought Greece to the brink of bankruptcy.

Tsipras, who led the country between 2015 and 2019, railed against harsh policies imposed by international bailout lenders but fell out of favor with voters as the country climbed out of recession.

He resigned following his third successive general election defeat.

Voters’ return to mainstream parties following three successive international bailouts has been more uneven on the left. The hardline Greek Communist Party has roughly doubled its support over the last four years to reach 10% in recent polls.

The resignations in Athens were matched at the European Parliament, where Syriza has lost several lawmakers, including veteran politician Dimitris Papadimoulis, a vice president of the assembly, would quit the party Thursday.

In a party statement, Syriza said many of the dissenters has ignored repeated and public invitations made by Kasselakis to join him in reforming the party.

Their actions, the statement said, “will be judged by history.”