Armenia and Azerbaijan agreed on Tuesday to an immediate ceasefire after a recent surge of fighting in the disputed region of Nagorno-Karabakh, the TASS news agency reported, citing Armenia's Defence Ministry.
"Operations along the line of contact between the Azerbaijani and Armenian forces have been suspended from noon local time [0900 GMT] on April 5 upon the agreement of the parties," the Armenian ministry was quoted as saying.
Azerbaijan's Defence Ministry confirmed to the Interfax news agency that a ceasefire deal had been reached.
The two former Soviet republics have fought for decades over the Nagorno-Karabakh region, populated primarily by Armenian Christians but recognized by the United Nations as part of predominantly Muslim Azerbaijan.
Russian, French and US diplomats who co-chair a mediation group set on resolving the long-standing conflict travelled to Nagorno-Karabakh on Tuesday, following consultations at the Organization for Security and Cooperation in Europe (OSCE) headquarters in Vienna, diplomats told dpa.
"The deterioration of the situation on the ground demonstrates the need for an immediate negotiation, under the auspices of the co-chairs, on a comprehensive settlement," the so-called Minsk Group said in a written statement.
Armenia and Azerbaijan have traded blame for sudden violence that reportedly erupted on Friday night. The fighting has been the most severe since a ceasefire was agreed in 1994.
The eruption of violence has happened amid wider regional tensions.
Armenia is in a military alliance with Russia, while Azerbaijan enjoys close ties with Turkey. Relations between Russia and Turkey are currently tense as they back opposing sides in the Syrian civil war.
Azerbaijan's Defence Ministry said in a statement on its website Monday that 170 soldiers had died in the recent clashes.
Armenian President Serzh Sargsyan told OSCE representatives on Monday that the conflict has the potential to devolve into an all-out war.
Sargsyan was scheduled to visit German Chancellor Angela Merkel on Wednesday for talks expected to focus on the heightened regional tensions.
According to Armenia's Defence Ministry, Azerbaijani troops started the fighting with an offensive involving tanks and artillery, to which Armenian forces responded by shooting down a combat helicopter and destroying several tanks and drones.
Azerbaijan denied the allegations, saying its soldiers were reacting to heavy attacks from the Armenian side.