The court upheld a decision made in May to reject a European Court of Human Rights ruling that Ocalan be retried on the grounds that his original trial in 1999 was unfair.

The PKK leader is currently languishing in a Turkish prison after a death sentence was commuted to life imprisonment in 2002 after Turkey abolished the death penalty.

A Turkish law passed in 2003 allows a retrial if a conviction is quashed by the European court, but is not retroactive, meaning that Ocalan and around a hundred others are not eligible.

A retrial of Ocalan, considered public enemy number one in Turkey, would likely cause a storm in Turkey, putting the government of Recep Tayyip Erdogan in a tricky position and exacerbate nationalism in his country.

Fighting between the PKK and Turkish security forces has killed more than 37,000 people since 1984. The group is deemed a terrorist organisation by Turkey, the European Union and the United States.

The ruling came the same day as the victory in the European Court of Human Rights for a Turkish journalist and newspaper owner convicted in Turkey for disseminating separatist propaganda on behalf of the PKK.

The charges were based on the fact that in 2000 the two men, Cihan Capan and Halis Dogan, had published in Ozgur Bakis a letter and an article written by Murat Karayilan, among others, one of the leaders of the PKK.

Dogan has been fined and Capan fined and sentenced to 13 months imprisonment. Capan had left for Switzerland so the sentences were not enforced. The two were also convicted for an earlier article deemed to be propaganda on behalf of an armed organisation.

Turkey violated the two men's rights to freedom of expression and to a fair trial, the Strasbourg court said in a statement, awarding 5,000 euros (6,300 dollars) to Capan and 7,000 euros to Dogan, plus costs.