YEREVAN/BAKU (Reuters) - Sensitive to the threat of wider confrontation, Russia and Turkey are for now limiting involvement in the Nagorno-Karabakh conflict to providing humanitarian assistance and some military aid.Ankara sees its strong backing for Azerbaijan over the fighting with ethnic Armenians in the mountain enclave as part of efforts to boost Turkey’s international clout. Moscow is determined to defend its own interests in the South Caucasus. But neither wants to be sucked into an all-out war, and private military contractors say Moscow and Ankara are largely turning a blind eye to the role of mercenaries - possibly fighting on both sides - to avoid stoking tensions. NATO member Turkey, which has stepped up arms supplies to Azerbaijan in recent years, is likely to refrain from deeper military involvement if its ally continues to advance in Nagorno-Karabakh, military and political analysts said. Russia, which has a defence pact with Armenia, also has good relations with Azerbaijan and is unlikely to become directly involved militarily unless Azerbaijan launches a deliberate attack on Armenia, they said. “The fundamental question is: does the Kremlin want the return of Nagorno-Karabakh to Azerbaijan?” said Pierre Razoux, academic director at France’s Mediterranean Foundation of Strategic Studies.