Lawmakers backed the candidacy of the Kremlin-supported veteran politician with 77 to 17 votes, after his second and final term as president ended last week.
The opposition denounced the vote - which makes Sargsyan Armenia’s top leader under a new parliamentary system of government - saying the 63-year-old lacked popular support.
Earlier in the day, several thousand demonstrators marched through the center of the capital Yerevan and staged sit-in protests outside government buildings.
Protesters blockaded the entrances to about a dozen government buildings, including those housing the foreign ministry and the central bank.
Ahead of the vote, Sargsyan blamed the opposition for rocking the boat.
“Extinct volcanoes should not wake up if we want to live in a prosperous Armenia, in a country of the rule of law. And volcanoes will not wake up if no one provokes them.”
Opposition leader Nikol Pashinyan urged Armenians to take to the streets en mass.
“I proclaim today the start of a peaceful velvet revolution in Armenia,” he told a rally in Yerevan earlier in the day, calling on supporters to “paralyze the work of all government agencies.”
Rallies were also held in the country’s second- and third-largest cities of Gyumri and Vanadzor. Police said 14 demonstrators were briefly detained.
On April 16 police used stun grenades as protesters sought to break through a barbed wire cordon in the center of Yerevan in an effort to get to the parliament building.
Authorities said 46 people including six police and opposition leader Pashinyan required medical help. Sargsyan, a shrewd former military officer, has been in charge of the landlocked South Caucasus nation of 2.9 million since winning a presidential vote in 2008.
Hurriyet Daily news
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