Armenia’s parliament is set to decide whether to back opposition leader Nikol Pashinyan as prime minister as his supporters rally in the capital.
Mr Pashinyan, who has led weeks of anti-government protests that forced former Prime Minister Serzh Sargsyan to resign, is the only candidate.
He warned MPs of a “political tsunami” if they did not back him.
Armenia’s ruling Republican Party said earlier it would not put up a candidate, in a bid to ease tensions.
But the protest leader said that there were moves aimed at halting his bid and he urged protesters to stay on the streets in the centre of Yerevan to prevent the Republican Party from “stealing the people’s victory”.
Mr Sargsyan, who had served 10 years as president, stepped down last month days after being sworn in as PM. He had been accused of trying to cling to power.
All 47 opposition members of parliament have pledged to vote for Mr Pashinyan, but he will need votes from six Republican Party deputies to win the majority he needs in the 105-seat house. The Republican Party has dominated Armenian politics since 1999.
Mr Pashinyan, who has said he will rid Armenia of corruption, poverty and nepotism, called on his supporters to rally as parliament convened.
— rayhan demytrie (@rayhandemytrie) May 1, 2018
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In an overnight video address on Facebook he warned supporters that the former president was asking his party to obstruct his election.
The protest leader asked people to meet at Republic Square in the capital, Yerevan, to celebrate what he called “the public victory over hopelessness, emigration and uncertainty”. An estimated 20,000 people gathered as the protest leader addressed parliament.
Mr Pashinyan, 42, has said he wants to call snap elections.
“Take this step,” he urged MPs, “and you will serve the homeland and the people, helping them to exit this 10-year internal political crisis, helping them to finally eradicate hopelessness from Armenia.”
What has happened in Armenia?
Demonstrators poured on to the streets of Yerevan last month in protest at Serzh Sargsyan’s move from the presidency to the post of prime minister.
In 2015, Armenians voted in a referendum marred by irregularities to shift their country from a presidential to a parliamentary system, stripping the presidency of its powers and giving them to the prime minister. Mr Sargsyan had initially vowed he would not seek to stay in power.
The protests surged on 17 April when he was elected prime minister by parliament within days of leaving the presidency.
Mr Pashinyan then met his rival for talks, which broke down within minutes when he called for the prime minister’s resignation and Mr Sargsyan accusing protesters of blackmail.
Mr Pashinyan and some 200 protesters were then arrested.
However, Mr Pashinyan was soon released and the prime minister resigned admitting he had “got it wrong”.