Almost 78% of voters in Russia have approved amendments to the constitution that will allow Vladimir Putin to stay in power until 2036, election officials said after all the votes were counted.

In the week-long balloting that concluded on Wednesday, 77.9% voted for the changes and 21.3% voted against, with all precincts counted by Thursday morning, Russia’s Central Election Commission said.

The turnout exceeded 64%, according to officials, with the reported numbers reflecting the highest level of voter support for Mr Putin in 10 years.

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In the 2018 presidential election, 76.7% of voters supported his candidacy, while in the 2012 election only 63.6% did.

But Kremlin critics say the numbers are false, with an unrealistic approval rating for the Russian leader amid widespread frustration over declining living standards.

“A record in falsifying votes has been set in Russia,” opposition politician Alexei Navalny said in a Facebook post. “The announced result has nothing whatsoever to do with the people’s opinion.”

The president’s approval rating was at 59% in May, according to the Levada Centre, Russia’s top independent pollster. That was the lowest in two decades.

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The week-long plebiscite was tarnished by widespread reports of pressure on voters and other irregularities, with independent election observers criticising the voting procedure as having a complete lack of transparency and independent control.

For the first time in Russia, polls were kept open for a week to bolster turnout and avoid election-day crowds amid the coronavirus pandemic — a provision Kremlin critics denounced as an extra tool to manipulate the outcome, as ballot boxes remained unattended at night.

Observers also pointed to the relentless pressure state and private employers put on their staff to vote, monitoring that was hindered by bureaucratic hurdles and virus-related restrictions, and the dubious legal standing of the early voting.