Turkish security forces are working hard to secure the safe release of the three who were seized by Kurdistan Workers Party (PKK) rebels on July 8 during a climbing expedition to Mount Ararat in Agri province, governor Mehmet Cetin said.

"In light of the information we have, I can comfortably say that the members of the PKK terrorist organization are still in the Agri region with the hostages," Cetin said. "We also have information that the hostages are in good health."

The governor said security forces were careful to avoid attempting a rescue operation that could lead to an armed clash and endanger the lives of the kidnapped tourists.

"Our main target is to make sure that the hostages are not harmed. We are also trying to prevent the terrorist organization from leaving (Turkey) and fleeing" abroad, he said.

The PKK said last week that it would hold the hostages until Berlin ends a crackdown on its militants and supporters in Germany, home to about 2.4 million immigrants from Turkey, including about 600,000 Kurds.

Earlier this week, a PKK spokesman also demanded that Ankara halt military operations in Agri as a condition for the climbers' release.

German leaders have dismissed the rebels' demand as blackmail and called for the immediate release of the hostages.

The PKK, listed as a terrorist organisation by Ankara, the European Union and the United States, has been fighting for self-rule in Turkey's Kurdish-majority east and southeast since 1984. The conflict has claimed more than 37,000 lives.

The group has in the past kidnapped soldiers, policemen, tourists and journalists, among others, but it is not a tactic it usually employs.