Updated

Russian President Vladimir Putin is holding a joint meeting with the leaders of Azerbaijan and Armenia, as concerns mount over the escalation of fighting over the South Caucasus region Nagorno-Karabakh.

Putin met Sunday with Armenian President Serge Sarkisian and Azerbaijan President Ilham Aliyev in Sochi to discuss rising tensions in the disputed territory, where 19 soldiers were killed in the past week.

Nagorno-Karabakh is a part of Azerbaijan but the region and some surrounding territory have been under the control of Armenian soldiers and local Armenian forces since a 1994 cease-fire ended a separatist war. Since then, there have been sporadic clashes.

Years of diplomatic efforts under the auspices of the Organization for Security and Cooperation in Europe have made little visible progress in resolving the dispute.