Mustafa Sarikaya, 46, was detained last week after airport police found a fake passport among his belongings and charged him with illegal entry.

But the former deputy chairman of the now-defunct Democratic Society Party (DTP) was released after persuading a court that his life was in danger in Turkey, where he has spent a total of 20 years in prison.

Sarikaya was travelling from Paphos in Cyprus to Sofia, Bulgaria.

Turkey's shortcomings in respecting political rights have been among numerous obstacles holding up its accession talks with the European Union.

The decision by Turkey's constitutional court in 2009 to dissolve the DTP for alleged links with the separatist Kurdistan Workers' Party (PKK) had been criticised by the EU's Swedish presidency at the time.