Turkey's third-largest political party, the pro-Kurdish HDP, said on Tuesday the court case targeting it is the culmination of a political effort to break it up.
A top state prosecutor filed the case against the Democratic Peoples' Party (HDP) in March 2021, seeking a ban over its alleged links to Kurdish militants. The party denies such ties.
The court accepted the indictment in June following a years-long crackdown under President Tayyip Erdogan in which thousands of HDP members have been tried on mainly terrorism-related charges.
Aside from closing the party, the indictment also calls for 451 HDP members to be banned from politics for five years, which would cover the elections set for June of 2023.
Umit Dede, a HDP deputy chairman, said after submitting its main written defence to the constitutional court that the indictment was a "political document".
"This document is the last link in the attacks which have been launched against the HDP since 2015," he told reporters outside the courthouse. "It is being used as part of an operation to push the HDP out of democratic politics."
"They wanted to fabricate a legal cover to liquidate the HDP," he said, adding that the party was being targeted because of its previous electoral success.
The HDP won 11.7% of votes in the 2018 election and has 56 MPs in the 600 seat assembly. Opinion polls show falling support for Erdogan's ruling AK Party ahead of next year's parliamentary and presidential elections, with HDP support holding relatively steady.
Turkey has a long history of shutting down political parties, including pro-Kurdish ones. Critics say its judiciary is subject to political influence, a claim denied by the AK Party and its nationalist MHP allies.
The HDP's law commission said the court would next set the dates for oral presentations to be made in the case, first by the prosecutor's office and then by the HDP.
The court will then deliberate and reach a decision, for which there is no deadline, it said.
The indictment says the HDP acts together with the Kurdistan Workers Party (PKK) militant group, and aims to undermine state unity. The PKK is designated a terrorist group by Turkey, the United States and European Union. It has fought an insurgency since 1984 in which more than 40,000 people have been killed.
(Reporting by Daren Butler; Editing by Jonathan Spicer and Alison Williams)