Turkey's top court on Friday closed the country's main pro-Kurdish party for having links to PKK Kurdish rebels in a ruling that could undermine efforts to end a long-running conflict with the separatists.
The European Union, which Turkey hopes to join, had warned that banning the party would violate Kurdish rights.
The Constitutional Court voted unanimously to ban the Democratic Society Party (DTP) after it found the party guilty of cooperating with the Kurdistan Workers' Party (PKK) separatist guerrilla group.
PKK guerrillas have fought for 25 years for a Kurdish homeland in southeastern Turkey.
The court ruling imposes a five-year ban from politics on 37 members of the DTP, the only Kurdish party in parliament, and follows the banning of several similar parties in the past. The expelled lawmakers included party leader Ahmet Turk, The Associated Press reported.
"The DTP's closure was decided due to its connections with the terror organization and because it became a focal point of the activities against the country's integrity," Constitutional Court Chairman Hasim Kilic said as he announced the verdict.
Conflict cost 40,000 lives
Eyeing EU membership, Prime Minister Tayyip Erdogan's Islamist-rooted AK Party has worked to improve Kurds' cultural rights with the hope of ending a conflict that has cost more than 40,000 lives.
Turkey's Kurdish population, whose language was outlawed for years, has long complained of discrimination.
Analysts fear that banning the DTP would strengthen the PKK's hand by undermining confidence both in the democratic process and the government's reform initiative.
The ruling threatens to increase instability ahead of a general election set for 2011. The government is trying to steer the economy back from a deep recession.
The case was brought by Turkey's Chief Prosecutor Abdurrahman Yalcinkaya, who tried unsuccessfully to close down Erdogan's party in 2008 on grounds it contravened the country's secular constitution.