"Kesbir cannot be extradited to Turkey," the Dutch Supreme Court said in a statement on its website.

"If Turkey makes new promises with more solid guarantees that Kesbir will be treated properly after extradition this ban could be lifted," the court's spokeswoman Eveline Hartogs told AFP.

"Turkey's guarantees (that Kesbir would not be tortured) were too general," Kesbir's lawyer Jacques Sluysmans said.

He added that his client was relieved by the ruling.

"Guaranteeing her a fair trail and saying measures will be taken to ensure she will not be mistreated... in line with international treaties... is not sufficiently specific... for a person like Mrs. Kesbir," Sluysmans added.

"On a state level such a consensus exists but how can they prevent her from falling victim to vindictive actions by individual police officers or prison wardens?"

The PKK has fought for Kurdish self-rule in southeast Turkey since 1984. It called off a five-year unilateral ceasefire in June 2004.

Kesbir, as PKK leader, worked alongside Osman Ocalan, the brother of former PKK leader Abdullah Ocalan who has been serving a life sentence in Turkey since 1999.

She is accused by Turkey of taking part in at least 25 attacks in eastern Turkey between 1993 and 1995. She denies any involvement in the attacks and claims she dealt only with the women's issues as a member of the PKK's presidential council.

Kesbir was arrested at Amsterdam's Schiphol airport in September 2001. She has tried to apply for political asylum but her demand was rejected so technically she is residing in the Netherlands illegally.

In September 2004 Dutch Justice Minister Piet Hein Donner authorized her extradition, saying on the basis of assurances from Ankara that Kesbir would get a fair trial in line with international law.

Kesbir appealed the extradition saying that she faced torture and would not get a fair trial. She was released in January 2005 after an appeals court decided that there was "a discrepancy in what the Turkish government wants and what happens on a lower level in police stations and prisons".

The justice ministry had appealed this ruling to the Supreme Court but it upheld the ban. The ministry could not be reached for comment Friday.

Last week the Council of Europe's Committee for the Prevention of Torture released a report saying that although abuse of prisoners is on the decline in Turkey it remains a problem, particularly in police stations.

The committee also remarked that the tightening of the legal protection for prisoners in custody had led to an increase in abuse carried out in isolated locations outside of police stations and prisons.