UPDATE 1-Kremlin says Putin making 'every effort' to de-escalate Armenia-Azerbaijan hostilities

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Sept 13 (Reuters) - Russian President Vladimir Putin is doing everything he can to help de-escalate hostilities between Armenia and Azerbaijan, the Kremlin said on Tuesday.

"It is difficult to overestimate the role of Russia, and the role of Putin personally" in mediating between the two countries, Kremlin spokesman Dmitry Peskov told reporters.

"The president is making every effort to contribute to the de-escalation of tensions on the border. These efforts are continuing," he added.

Both Armenia and Azerbaijan have blamed each other for overnight clashes along the border.

A Moscow-brokered ceasefire collapsed after less than an hour on Tuesday morning, although the intensity of fighting has reduced, Armenia's Prime Minister Nikol Pashinyan said in an address to parliament.

The new flare-up of decades-old hostilities between the south Caucasus countries has fuelled fears that a second fully-fledged war could break out in the post-Soviet world in addition to Russia's invasion of Ukraine. (Reporting by Reuters)