Ms Navalnaya said she had drawn hope from the huge crowds that turned out last week for the funeral of the prominent opposition leader, who died in prison last month.

Her call for Russians to turn out to vote at the same time at noon on 17 March - a form of protest in tightly controlled Russia - echoes a call made by her late husband before his death.

His idea was that people could register a protest, without any risk of arrest, by all turning out en masse at the same time on election day in cities across the country.

In a video posted to YouTube, Ms Navalnaya said: "We need to use the election day to show that we exist and there are many of us.

"We are real, living people, and we are against Putin."

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Navalny's funeral lifts spirits

Ms Navalnaya said people had a choice: cast a ballot for another candidate, spoil their ballot or write "Navalny" in big letters on it.

"And even if you don't see the point in voting at all, you can just come and stand at the polling station, and then turn around and go home," she added.

The Kremlin has strongly denied accusations by Ms Navalnaya that Vladimir Putin had Mr Navalny killed, and has declined to comment on the public response to his death and funeral.

His death certificate said he died of natural causes at the age of 47.

President Putin is widely expected to triumph in the elections and secure another six year term in office, with no candidates left in the process who are critical of him.