Armenian Prime Minister Nikol Pashinyan has warned of an attempted military coup, after the country's armed forces said he and his cabinet must resign.

The army "must obey the people and elected authorities," he told thousands of supporters in the capital Yerevan. His opponents held a rival rally.

The military's top brass was angered by the PM's sacking of a commander.

Mr Pashinyan has faced protests after losing last year's bloody conflict with Azerbaijan over a disputed region.

Nagorno-Karabakh is an enclave internationally recognised as part of Azerbaijan but which had been controlled by ethnic Armenians since a 1994 truce.

During the six-weeks of fighting late in 2020, Azerbaijan not only recaptured areas around the enclave but also took the key town of Shusha inside it.

Under the Russian-brokered deal that emerged shortly afterwards, Azerbaijan keeps the areas it has captured. Hundreds of Russian peacekeepers are deployed in the disputed area.

What is Pashinyan's defence?

In a Facebook video post on Thursday, Mr Pashinyan, 45, said he considered a statement by the military earlier on Thursday an "attempted military coup".

He urged his backers to gather on Republic Square in the heart of Yerevan, and was seen shortly afterwards surrounded by thousands of supporters on the streets of the city.

"The army is not a political institution and attempts to involve it in political processes are unacceptable," he told his supporters.

But he invited the opposition to hold talks on how to resolve the crisis, stressing that any change in power must take place "only through elections".

Meanwhile, opposition supporters staged a rival demonstration in the capital, insisting that Mr Pashinyan must go.

Vazgen Manukyan, one of the opposition leaders, urged the crowds to start blocking the parliament, saying lawmakers should be brought in to vote for Mr Pashinyan's dismissal.

"Get ready, we will stay here all night and will block the street with barricades," he was quoted as saying by the Armenpress news agency.

Mr Pashinyan, a former journalist, took office after leading a peaceful 2018 revolution in the post-Soviet state.

He has recently survived several attempts in parliament to dismiss him. (BBC)

· PHOTO: Nikol Pashinyan, Armenian Prime Minister (centre) gave the thumbs up as he walked in Yerevan surrounded by hundreds of supporters and police (REUTER PHOTO)

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