Armenia has said the current flare-up is between Karabakh and Azerbaijan.

Russian Foreign Minister Sergey Lavrov talked to his Azerbaijani and Armenian counterparts on the phone Saturday to emphasized the need for the truce to hold, according to Russia's Foreign Ministry.

Arayik Harutyunyan, leader of the contested region, welcomed the new peace effort, saying in a statement, "The Republic of Artsakh confirms readiness to observe the humanitarian truce on a reciprocal basis," in line with the ceasefire agreements brokered by Moscow on Saturday and one week ago.

Before the latest ceasefire attempt Saturday, Azerbaijan accused Armenia of a rocket attack against its second-largest city, Ganja, killing at least 13 civilians -- including three children -- and wounding more than 50 others.

Azerbaijan President Ilham Aliyev called the missile strike a "cowardly shelling" that "cannot break the will of the Azerbaijani people."

The attack occurred in the early hours of Saturday morning and targeted civilian quarters in the central part of the city, according to a statement from the Azerbaijani prosecutor's office.

Azerbaijani presidential adviser Hikmet Hajiyev accused Armenia of using ballistic missiles in the attack and said authorities had evidence to support the claim, according to a Twitter post.