NATO Secretary-General Jaap de Hoop Scheffer said on Monday in Ankara that the Kurdish Workers' Party (PKK) was certainly a terrorist organization.
De Hoop Scheffer, who is currently paying a working visit to Ankara, made the remarks at a news conference after his meeting with Turkish Prime Minister Recep Tayyip Erdogan.
He said that fight against terrorism required an international cooperation, adding that the United States, the European Union and the United Nations included PKK in their lists of terrorist organizations.
He recalled that NATO prepared a list of terrorist organizations in 2003 in which PKK was described as a terrorist organization.
De Hoop Scheffer highlighted importance of cooperation between NATO and the EU in fight against terrorism.
In June 2004, the PKK called off a ceasefire declared five years ago.
Since then, more than 1,000 militants are believed to have infiltrated Turkey from their bases in northern Iraq and violence has resurged in Turkey with at least 200 Turkish soldiers killed this year.
More than 37,000 people have been killed since the rebel group took up arms against Ankara for self-rule in the Kurdish-dominated southeastern Turkey in 1984.