With bad blood flowing between Turkey and Russia since Ankara shot down a Russian warplane in Syria in November, the latest wave of violence in Nagorny-Karabakh could have wider implications.

Azerbaijan and Armenia-backed rebels in Karabakh -- which was seized from Azerbaijan in a war in the early 1990s -- agreed Tuesday to a ceasefire to stop the worse violence in decades that has claimed at least 64 lives since Friday.

But the differing reactions of Ankara and Moscow to the surge in violence has underscored how the crisis could divide more than just the warring parties.

Turkish President Recep Tayyip Erdogan on Monday emphatically threw his weight behind ally Azerbaijan, saying Turks stood "side-by-side with our brothers in Azerbaijan" and predicting that Baku would "one day" retake the mountainous region.

Moscow has a military alliance with Armenia, where it maintains a base, but supplies both sides with weapons.

Russian President Vladimir Putin did not take a side in the conflict between the two ex-Soviet countries, instead urging an "immediate ceasefire" over the weekend.

Below is an outline of Russian and Turkish positions on Nagorny-Karabakh:

- RUSSIA -

Ex-Soviet master Moscow, like the rest of the world, has not recognised Nagorny-Karabakh as Armenian territory and on Tuesday was "very energetically" trying to defuse the standoff, according to Kremlin spokesman Dmitry Peskov.

Though it supplies both countries with weapons, there is some evidence Moscow has been selling arms to energy-rich Baku at a higher rate and cash-strapped Armenia at a lower price, according to Magdalena Grono of the International Crisis Group.

Moscow has historically served as the key mediator since the war in Nagorny-Karabakh ended with an inconclusive ceasefire in 1994, but its reputation as peacemaker has been eroded by its seizure of Crimea and role in a bloody conflict in east Ukraine, said Alexander Malashenko of Carnegie Moscow Center.

The Kremlin would have the most to lose if Azerbaijan seizes Armenian-controlled territory, Malashenko said, as Russia risks losing Azerbaijan entirely as a partner in the region if it comes to Armenia's aid.

"Russia is at a dead end," he said.

A protracted conflict would "reinforce Turkey's influence in Azerbaijan," which may also reverberate in Russia's volatile North Caucasus region, Russia's independent daily Vedomosti said Monday.

- TURKEY -

Ankara has come out strongly in support of its Turkic-speaking historic ally Azerbaijan during the latest clashes, with Prime Minister Ahmet Davutoglu telling parliament Tuesday Turkey will back Baku "all the way until the apocalypse."

Turkey has no diplomatic relations with Armenia because of the century-old dispute over the mass killings of Armenians in the Ottoman Empire, which Yerevan calls a genocide but Ankara refuses to admit as such.

Public opinion in Turkey shows "strong solidarity" with Azerbaijan due to shared national identity, said Can Kasapoglu, an analyst with the Center for Economics and Foreign Policy Studies in Istanbul.

But despite the high tensions with Moscow, "Ankara would still avoid a regional war," he said, instead opting for "capacity building measures to support its ally".