The United States and Europe have criticised a move by Turkey towards banning the pro-Kurdish Peoples' Democratic Party (HDP), a week before EU leaders are due to discuss strained relations with Ankara at a summit.
A Turkish prosecutor filed a case with the constitutional court on Wednesday demanding a ban on the HDP over alleged ties to Kurdish militants, the culmination of a years-long crackdown against the third largest party in parliament.
The move marks the revival of a long history of Turkey banning political parties, including pro-Kurdish ones.
The US State Department said dissolving the HDP "would unduly subvert the will of Turkish voters, further undermine democracy in Turkey, and deny millions of Turkish citizens their chosen representation".
The prosecutor's announcement of the case came on the same day that Turkey's parliament stripped a prominent HDP deputy of his parliamentary status.
"Unapologetically (moving) towards the end of pluralism. What reaction does Turkey expect now from the European Union? A positive agenda?" said Nacho Sanchez Amor, the European Parliament's rapporteur on Turkey, which is a candidate for EU membership though accession talks have been stalled for years.
The HDP had recently come under intensified pressure, with nationalist allies of President Tayyip Erdogan's AK Party calling for it to be banned over alleged ties to the outlawed Kurdistan Workers Party (PKK) militant group.
That coincided with falling poll support for the AKP and its nationalist allies as they battle the economic fallout of the coronavirus pandemic. Elections are not scheduled until 2023.
Presidential communications director Fahrettin Altun said in the first government reaction it was "an indisputable fact that HDP has organic ties to PKK", noting Turkey, the United States and the European Union consider it a terrorist organisation.
"HDP's senior leaders and spokespeople, through their words and deeds, have repeatedly and consistently proved that they are the PKK's political wing," he said.
Devlet Bahceli, leader of the Nationalist Movement Party (MHP), also hailed the move: "The HDP is a criminal organisation disguised in a political cloak. It is a historic and moral duty for it to be shut and never to be reopened under another name."
The HDP has said it would regroup in a new party if banned, though the Haberturk news website cited the indictment as saying the prosecutor demanded a political ban for more than 600 HDP officials - a severe obstacle to any such move.
The HDP, which won 11.7 per cent of the vote in a 2018 parliamentary election and has 55 seats in the 600-member parliament, accused the AKP of shaping politics through the courts. It denies any links to the militants.
The PKK has fought an insurgency against the state in mainly Kurdish southeast Turkey since 1984. More than 40,000 people have been killed in the conflict.