Dressed in impeccable camouflage fatigues with Kalashnikovs slung over their shoulders, Russian peacekeepers stand guard along the last road linking Armenia with the restive region of Nagorno-Karabakh

An opposition leader in Armenia has been arrested and accused of preparing to kill the prime minister, his lawyer said, adding to the political turmoil created by a controversial peace deal with neighbouring Azerbaijan.

Thousands of Armenian demonstrators, chanting "Nikol is a traitor", demanded Prime Minister Nikol Pashinyan resign on Wednesday over a ceasefire that secured territorial advances for Azerbaijan in Nagorno-Karabakh after six weeks of fighting.

Armenia and Azerbaijan agreed on a deal with Russia to end weeks of fierce clashes over Nagorno-Karabakh on Tuesday, after a string of Azerbaijani victories in its fight to retake the disputed region

Azeris celebrated on the streets of Baku after President Ilham Aliyev said on Sunday his country's forces had taken Shusha, the second-largest city in the Nagorno-Karabakh enclave, but Armenian officials denied the city had been captured.

Armenia reported Saturday that "fierce combat" with Azerbaijani forces took place overnight near the town of Shusha, a key stronghold in the disputed Nagorno-Karabakh region.

A third attempt at halting weeks of fighting over Nagorno-Karabakh collapsed quickly on Monday with Armenia and Azerbaijan trading accusations of violating the US-brokered ceasefire within minutes.

New fighting erupted between Azerbaijan and ethnic Armenian forces on Sunday over the mountainous enclave of Nagorno-Karabakh as both sides blamed each other for blocking a peaceful settlement to the conflict.

Close quarters, poor ventilation and no masks: in the cellars of Stepanakert, the capital of the disputed Nagorno-Karabakh province, residents who have not fled fierce fighting may be safe from shelling, but not coronavirus.

Azerbaijan's Ministry of Defence said that Armenian armed forces fired ballistic missiles towards its territory in Gabala and Kurdamir districts, north of the country, targeting civilians.

The foreign ministers of Armenia and Azerbaijan were in Moscow on Wednesday for meetings with Russia's top diplomat Sergei Lavrov as world powers seek to halt fighting over Nagorno-Karabakh.

Armenia and Azerbaijan said on Tuesday their foreign ministers would meet US Secretary of State Mike Pompeo in Washington on Friday in efforts to end the heaviest fighting in Nagorno-Karabakh since the 1990s.