The Kurdish Workers' Party (PKK) warned Berlin of "negative consequences" resulting from their policy towards Kurds more than a week before three German climbers were kidnapped, according to a news report Saturday.
Attendees of a a Kurdish event in Cologne demonstrate against the ban of the broadcaster Roj-TV
Der Spiegel news magazine said the warning from the executive council of an organization called the "United Communities of Kurdistan" had called on the "Merkel government" to halt its "hostile policies against the Kurdish people and its liberation movement."
The weekly described the organization as second only to PKK leader Abdullah Ocalan, who is currently being held in Turkey, in the guerrilla leadership.
German federal police had also received a warning from their Turkish counterparts that there indications of a pending attack by Kurdish separatists, Der Spiegel said.
Three weeks ago, the German Interior Ministry banned the Kurdish television broadcaster Roj-TV.
Merkel makes appeal
Protestors in Berlin hold a flag showing PKK founder Abdullah Ocalan
German Chancellor Angela Merkel appealed Saturday for the release of the three mountaineers but she insisted that Germany would not be blackmailed.
Speaking to the Sunday edition of the mass-circulation Bild newspaper, Merkel said German officials were working closely with their Turkish counterparts to secure the release of the men, seized near Mount Arafat late Tuesday.
The German chancellor said she would raise the issue with Turkish Prime Minister Recep Tayyip Erdogan when she meets him in Paris on Sunday at the launch of the Union for the Mediterranean.
The PKK, which has claimed responsibility for taking the three men hostage in eastern Turkey, is listed as a terrorist organization in the European Union and the United States. The PKK has been fighting for Kurdish autonomy since 1984.
German climbers in Turkey on July 9, after their friends had been abducted and before their return to Germany
Lars Holger Renne, 33, Martin Georg, 47, and Helmut Johann, 65, all from the southern German state of Bavaria, were taken hostage late Tuesday when a group of five PKK guerrillas raided a 3,200-meter camp on Mount Ararat in eastern Turkey.
Their 10 fellow climbers were unharmed and returned to Germany late Friday.
The pro-Kurdish Democratic Society Party on Friday offered to mediate to secure the release of three mountaineers, Turkey's Hurriyet newspaper reported on its website.
Helmut Johann, one of the mountain climbers who was kidnapped
"If there is any request from the German government or the families of the climbers, then we would see what we could do," Emine Ayna, chairperson of the DTP parliamentary group, said in a statement issued by the DTP's press office in the south-eastern province of Diyarbakir.
She added that no such request has been made. The DTP has close ties to the PKK, and refuses to describe the group as a terrorist organization. In November last year parliamentarians from the DTP acted to secure the release of eight Turkish soldiers taken hostage by the PKK.