"There is no military solution to this problem," Kouchner told reporters.

"Once again we appeal for restraint. This worsening of tensions is full of menace in a region that is already highly unstable."

"The situation is very dangerous. I am very worried," he said, noting the clashes came days after the Turkish parliament authorised cross-border military strikes against rebel Kurdistan Workers' Party (PKK) bases in northern Iraq.

The clashes erupted after a large group of PKK rebels infiltrated from northern Iraq and attacked the soldiers shortly after midnight Saturday.

Ankara says some 3,500 PKK fighters are based in northern Iraq, using it as a springboard for attacks on Turkish territory.

Kouchner argued that the Turkish army was powerless to strike at the remote mountain bases of the PKK.

But Turkey says it is running out of options other than military action as neither the United States nor Iraq have done enough to stamp out rebel bases.

More than 37,000 people have been killed since 1984 when the PKK, branded a terrorist group by much of the international community, took up arms fighting for self-rule in Turkey's mainly Kurdish southeast.