YEREVAN, Armenia (AP) — The Armenian parliament on Thursday called for an extraordinary session next week to vote on a new prime minister after the country was plunged into a political crisis with the abrupt resignation of its leader.

Serzh Sargsyan, who ruled the country for 10 years, surprised many when he stepped down as prime minister Monday amid massive anti-government protests.

Parliament said a vote will be held May 1 to elect a new leader, potentially leading the way out of the post-Soviet nation's biggest political crisis in years.

Nikol Pashinian, who leads the opposition and wants to be nominated for prime minister, held talks earlier Thursday with parliamentary factions to secure support for his candidacy. Sargsyan's party still holds a majority in the parliament, however.

Thousands of anti-government protesters rallied Thursday night in the main square of Yerevan, the capital. At the rally Pashinian called for talks Friday with Armenia's acting prime minister but showed no indication of backing down from positions that scuttled such talks on Wednesday.

"Either I will become prime minister or there won't be a prime minister in Armenia," he declared.

Acting Prime Minister Karen Karapetian walked out of the earlier talks, accusing Pashinian of delivering ultimatums.

Sargsyan won two presidential terms by a landslide before moving to the role of prime minister earlier this year. The population of this impoverished nation, however, has been disappointed by the perceived cronyism of Sargsyan and by rampant government corruption.

Opposition rallies began two weeks ago to protest what was seen as Sargsyan's attempt to stay in power indefinitely.

Tens of thousands of opposition supporters rallied Wednesday in Yerevan, calling for Pashinian to become prime minister. Protesters on Thursday morning blocked traffic on major roads around the capital, chanting "Victory!"

"There are more of us every day," said 30-year-old Samvel Nazaryan, who was waving the Armenian tricolor on a Yerevan street. "The wave of protest will wash away this government sooner or later."

The Kremlin is watching its small but strategic ally, where Russia has a military base, with concern. Moscow, however, has showed restraint in its reaction, insisting that the demonstrations are a domestic matter.

The Kremlin said Thursday that Russian President Vladimir Putin discussed the crisis on the phone with Armenian President Armen Sarkisian, Sargsyan's ally, and the Armenian foreign minister flew to Moscow to meet with Russia's foreign policy chief.

On Wednesday, Russia's ambassador to Yerevan met with Pashinian.

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Nataliya Vasilyeva contributed to this report from Moscow.

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