Turkish media say the prosecutor's office has started a legal process to shut the country's main pro-Kurdish political party, alleging it has ties to Kurdish rebels.
The reports say Turkey's chief prosecutor, Abdurrahman Yalcinkaya, filed a case at the Constitutional Court to ban the Democratic Society Party - the DTP.
The move follows the DTP's call for autonomy for the mainly Kurdish region of southeastern Turkey as a way to resolve more than two decades of separatist violence spearheaded by the Kurdistan Workers Party - the PKK.
In the past, Turkey has banned pro-Kurdish parties for links to PKK rebels.
Turkey has been pressing Iraq to crack down on PKK guerrillas who shelter in northern Iraq.
Turkey has also threatened cross-border military operations against the PKK.
Some information for this report was provided by AFP, AP and Reuters.