A UN envoy called on Turkey on Friday to help prevent a slaughter in the Syrian border town of Kobani at the hands of Islamic State fighters, saying he feared a repeat of the 1995 Srebrenica massacre when thousands died.
Staffan de Mistura, the United Nations' envoy to Syria, appealed to Ankara to let "volunteers" cross the frontier so that they can reinforce Kurdish militias defending the town that lies within sight of Turkish territory.
He revived memories of the breakup of Yugoslavia when Bosnian Serb forces marched into the town of Srebrenica, which was supposed to be under UN protection, and gunned down more than 8,000 Muslim men and boys at execution sites.
"Do you remember Srebrenica? We do. We never forgot and probably we never forgave ourselves," de Mistura told a news conference.
Turkey has stationed tanks on hills overlooking Kobani but so far refused to intervene without a comprehensive deal with the United States and other allies on the Syrian civil war. It has also prevented Turkish Kurds from crossing the frontier to reinforce their fellow Kurds defending the town.
"We would like to appeal to the Turkish authorities ... to allow the flow of volunteers at least and their own equipment in order to be able to enter the city and contribute to a self-defence action," de Mistura said in Geneva.
Predicting Kobani is likely to fall "if left unattended", he said self-defence with sufficient equipment to do so was an international human right.
While much of the population has already fled the Islamic State offensive, 500-700 mostly elderly people are still sheltering in Kobani.
Asked if he meant Turkey should allow arms supplies, de Mistura replied: "I said what I said: equipment can be many things."
In addition to the people in Kobani, about 10,000-13,000 were nearby in a border area between Syria and Turkey, and there was one last exit point out of the town.
"If this falls, the 700, plus perhaps the 12,000 people, apart from the fighters, will be most likely massacred," he said. "When there is an imminent threat to civilians, we cannot, we should not, be silent."
If the city fell, 400 km of the 900 km-long Syrian-Turkish border would be in Islamic State hands.
Former Bosnian Serb leader Radovan Karadzic is on trial in the Hague for war crimes, crimes against humanity and genocide, including for Srebrenica, Europe's worst massacre since World War Two.
De Mistura, who followed Kofi Annan and Lakhdar Brahimi into the role of UN Syria mediator, reiterated that there was no military solution to the Syrian war but said facts on the ground had changed since an international Geneva conference agreed ground rules for ending the conflict in 2012.
He said nobody would win the war and the emergence of Islamic State as a common enemy had provided an opportunity for local ceasefires and ending long-running sieges in Syria.
Asked if he would negotiate with Islamic State, said he was "authorised and expected to talk to anyone" if that produced a political solution or a humanitarian relief.
"But I am not proposing, I am not planning, and they are not asking to meet anyone of us," he said.