The new deal, slated to begin at midnight local time (4:00 p.m. ET Saturday), was announced earlier in the day after both sides accused each other of attacks in violation of the Moscow-brokered week-long peace agreement.
The dispute dates back to the collapse of the Soviet Union when Nagorno Karabakh declared independence from Azerbaijan and sparked a violent conflict that ended in a shaky ceasefire in 1994.
Armenia supported Nagorno-Karabakh, which in fact established an independence that is not recognized by most of the world. Although it is located on Azerbaijani territory, the region is populated and controlled by ethnic Armenians.
Armenia has said that the current flare-up is between Karabakh and Azerbaijan.
Russian Foreign Minister Sergei Lavrov spoke on the phone with his Azerbaijani and Armenian counterparts on Saturday to emphasize the need for a ceasefire, according to the Russian Foreign Ministry.
Arayik Harutyunyan, leader of the disputed region, welcomed the new peace efforts and said in a statement: “The Republic of Artsakh confirms its readiness to honor the humanitarian ceasefire on a mutual basis,” in line with that of Moscow on Saturday and a week ago.
Nagorno Karabakh is called Artsakh by the Armenians.
Ahead of the latest attempted ceasefire on Saturday, Azerbaijan accused Armenia of a rocket attack on its second largest city, Ganja, in which at least 13 civilians – including three children – were killed and more than 50 others were injured.
Azerbaijani President Ilham Aliyev called the missile attack “cowardly shelling” that “cannot break the will of the Azerbaijani people”.
The attack occurred in the early hours of Saturday morning and, according to the Azerbaijani prosecutor, was directed against civilian areas in the central part of the city.
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.
“Let the international community see the barbaric acts of Armenia against the civilian population,” added Hajiyev.
Videos and photos allegedly taken from the scene showed rescue workers clearing debris to reach survivors. Prosecutors said the officers were compiling a full list of victims.
Last weekend, after weeks of fighting, another temporary truce fell apart. The two countries exchanged allegations of breach of the agreement after victims were reported.
France has been calling for “an immediate end to hostilities” since fighting broke out between the countries on the morning of September 27.
Last week’s short-lived ceasefire came after UN High Commissioner for Human Rights Michelle Bachelet spoke about the suffering the conflict was causing civilians.
The Nagorno-Karabakh dispute has grown hot and cold since the 1994 armistice.
The region lies on Azerbaijani territory and is connected to Armenia by an expensive highway. It is heavily militarized and its armed forces have been backed by Armenia, which has a security alliance with Russia.
Tensions have increased since July, when clashes ripped the border between Armenia and Azerbaijan for several days.
CNN’s Aren Melikyan, Tim Lister and Arzu Geybulla contributed to this report.