ANKARA, Sept 21, 2025 (BSS/AFP) - Turkey's main opposition CHP was holding an extraordinary congress to re-elect its leader Sunday as the party fights off a barrage of what critics say are politically-motivated legal challenges.

The move comes as the Republican People's Party (CHP), seeks to shore up its leadership in the face of a potentially damaging lawsuit seeking to oust Ozgur Ozel as leader.

The lawsuit, which had its second hearing on Monday, aims to overturn the result of CHP's November 2023 congress which elected Ozel, on grounds of alleged vote rigging.

Taking place in Ankara, the capital, the CHP congress is looking to forge a strategy going forward in a move Ozel has described as "an entirely technical and legal manoeuvre" to protect the party's leadership.

At Sunday's gathering, 911 party members will vote sto re-elect Ozel, who is the only one running, party officials said.

Under his leadership, CHP's fortunes have improved significantly, with the party winning a huge victory over President Recep Tayyip Erdogan's AKP in the March 2024 local elections.

Since then, the party has been targeted by a wave of arrests and legal cases that peaked in March with the jailing of Istanbul's popular and powerful mayor Ekrem Imamoglu on corruption allegations that he denies.

The dramatic arrest and jailing of Imamoglu -- CHP's candidate for the 2028 presidential election -- sparked an outpouring of protest with Ozel leading huge protests that spread from Istanbul in the worst unrest Turkey has seen since 2013.

On September 2, a court ousted the leader of CHP's Istanbul branch, Ozgur Celik, after annulling the outcome of the October 2023, provincial congress that elected him and 195 others.

At the time, political analyst Berk Esen said the move was a "rehearsal" for the bigger case against the overall leadership that was effectively seeking to hobble it as an opposition force.

The next hearing in the CHP case is scheduled for October 24.

CHP's Istanbul branch will hold its own extraordinary congress on Wednesday to re-elect its leadership.