An ethnic Armenian soldier looks through binoculars near the village of Taghavard in the region of Nagorno-Karabakh, on January 11, 2021 [File: Artem Mikryukov/ Reuters]

Azerbaijan reports losses among its troops after large-scale border clashes with Armenia.

Armenia and Russia have agreed on joint steps to stabilise the situation along Armenia's border with Azerbaijan after deadly overnight clashes, officials in Yerevan said.

Armenia's defence minister Suren Papikyan said he spoke with his counterpart Sergei Shoigu on Tuesday and they both "agreed to take necessary steps to stabilise the situation".

Earlier, Armenia and Azerbaijan have both reported new border clashes that left an unknown number of Azerbaijani troops dead, in the latest flare-up between the arch foes who fought a war in 2020 over the contested Nagorno-Karabakh region.

Each side blamed the other for the fighting.

In a statement, Armenia's defence ministry said Azerbaijan launched "intensive shelling" against Armenian military positions in the direction of the cities of Goris, Sok, and Jermuk at 00:05am (20:05 GMT) on Tuesday. Azerbaijani troops used drones, as well as "artillery and large-calibre firearms," it said.

"Armenia's armed forces have launched a proportionate response," it added.

But Azerbaijan's defence ministry accused Armenia of "large-scale subversive acts" near the districts of Dashkesan, Kelbajar and Lachin on the border, adding that its army positions "came under fire, including from trench mortars".

"There are losses among [Azerbaijani] servicemen," it said, without giving figures.

According to Azerbaijani media, the two countries had agreed on a ceasefire early on Monday to halt the hostilities, but it fell apart minutes later.

The truce came into force at 9am local time (0500 GMT), according to media reports and a source, who asked not to be named, but it was broken soon after.

‘No military solution'
Russia is a key power broker in the region and an ally of Armenia through the Moscow-led Collective Security Treaty Organization.

Meanwhile, the United States said it was deeply concerned about reports of the attacks.

"As we have long made clear, there can be no military solution to the conflict," US Secretary of State Antony Blinken said on Monday. "We urge an end to any military hostilities immediately."

Turkey's foreign minister Mevlut Cavusoglu said that Armenia should cease provocations, and instead focus on peace negotiations and cooperation with Azerbaijan.

There have been frequent reports of fighting along the Armenia-Azerbaijan border since the end of their 2020 war.

Last week, Armenia accused Azerbaijan of killing one of its soldiers in a border attack.

In August, Azerbaijan said it had lost a soldier, and the Karabakh army said two of its troops had been killed and more than a dozen wounded.

The neighbours have fought two wars over the Nagorno-Karabakh region, the Armenian-populated enclave in Azerbaijan.

Conflict first broke out in the late 1980s, when both sides were under Soviet rule and Armenian forces captured swathes of territory near Nagorno-Karabakh - long recognised internationally as Azerbaijan's territory, but with a large Armenian population. About 30,000 people died in the ensuing conflict.

Azerbaijan regained those territories in the 2020 fighting, which ended with a Russian-brokered truce and thousands of residents returning to homes from which they had fled. More than 6,500 people lost their lives in the six-week war.

The leaders of both countries have since met several times to hammer out a treaty intended to establish a lasting peace.

During EU-mediated talks in Brussels in May and April, Azerbaijani President Ilham Aliyev and Armenian Prime Minister Nikol Pashinyan agreed to "advance discussions" on a future peace treaty.

Pashinyan on Tuesday held separate phone calls with Russian President Vladimir Putin, French President Emmanuel Macron, and EU's President Charles Michel on the latest clashes, according to the Armenian government.

Michel said the EU was "ready to make efforts to prevent further escalation" and said there was "no alternative to peace and stability in the region".

Pashinyan condemned the "provocative, aggressive actions" of the Azerbaijani armed forces and called for an "adequate response from the international community", the Armenian government said.