Opposition activists claim 80,000 attend demonstration over vote-rigging claims, as Gorbachev calls on Putin to resign

Tens of thousands have taken to the streets of Moscow to protest against allegedly fraudulent elections, as opposition leaders issued scathing personal attacks on Vladimir Putin in the hope of preventing his return to the presidency next year.

Mikhail Gorbachev has urged Putin to follow his own example and step down. Former leader Gorbachev said on Ekho Moskvy radio that if Putin stepped down now he would be remembered for the positive things he did during his 12 years in power.

Security sources said 80,000 people turned out for the four hour protest on Moscow's Sakharov Prospect, despite a freezing temperature of -5C. Police put the number at 29,000 while protest organisers said up to 120,000 had gathered.

Protesters waved banners, let fly balloons and called for Putin's ouster in the biggest protest yet against the powerful leader's rule.

"I see enough people here to take the Kremlin or White House right now!" opposition leader Alexey Navalny told the crowd.

"But we are a peaceful force – we won't do that, for now. But if these crooks and thieves continue to try to cheat us, to try to lie and steal from us, we will take [what's rightfully ours] by ourselves."

The protest, on a wide avenue named after leading Soviet dissident Andrei Sakharov, dwarfed a similar protest held two weeks ago. While that crowd was largely young and middle class, Saturday's protest also gathered many pensioners and first-time protesters, indicating that anti-government sentiment was growing.

"Russia can't go on like this," said Alexei Frolov, 26, a clothing shop manager. "Putin should stand aside; he looks out of touch with reality."

Frolov said he voted against the United Russia party in the early December parliamentary vote and became angry after seeing videos of ballot box stuffing online.

"When I looked at the crowds going to the first protests, I saw they were not cattle, but normal, happy people who just wanted to defend their rights. So this time I decided to come too."

Speakers issued attacks on Putin and called on voters to prevent his election in a 4 March presidential vote. A further protest was planned for after the long New Year's holiday.

"We are the 99%," Left Front leader Sergei Udaltsov said in a video message broadcast to the crowd. Udaltsov has been repeatedly jailed for minor offences in what his supporters say is a campaign to keep him off the streets. "The 1% are Kremlin bandits, criminal oligarchs, corrupted officials and other bastards."

Referring to Putin and Dmitry Medvedev, the president, he said: "The leadership – these tandem dwarves – is deathly dangerous for Russia."

Although able to unite a huge crowd against Putin, opposition leaders have struggled to unify around a concrete figure, although Navalny, recently released from jail following his participation in Russia's first post-election protest, was best able to rouse the crowd and has proven popular among many in the Moscow elite despite his nationalist views.

The oligarch Mikhail Prokhorov, who has received Kremlin approval to run for president as a relatively liberal candidate against Putin, showed up at the protest but did not address the crowd. Alexei Kudrin, a longtime Putin ally and former finance minister, made an unexpected appearance and joined the call for new elections.

"We believe that next year power will change peacefully and power will belong to who it should," Navalny said. "We warn that we will go out into the streets until they return what belongs to us. We are peaceful people but we can't be patient indefinitely."

Medvedev has attempted to appease the protesters by offering a package of election reforms and permitting them to gather. The police presence in Moscow was minimal on Saturday, although a helicopter hovered over protesters' heads.

Medvedev, due to leave the presidency after the March vote and long seen as being in Putin's shadow, was not a target for most protesters. They instead turned their wrath toward Putin. Several protesters carried condoms in reference to Putin's insult their protest symbol – a white ribbon – resembled contraceptives. Some were inflated and held like balloons, others dangled limply from coats or posters. Others held aloft posters comparing Putin to Muammar Gaddafi and Kim Jong-il.

Natalya Dikashvili, a 30-year-old advertising agency owner, stood alone holding a white rose and the orange flag that is the symbol of Solidarity, an umbrella liberal opposition organisation. "I don't know a single person who voted for United Russia but the official result said they got almost 50%," she said. "We need clean, honest elections so that there is a real choice. We need fairness."

What response would satisfy her from Putin and the ruling elite? "That they would all go away so that we can start again,"she said.

Yelena Savrayeva, 42, the director of a publishing firm, had a white ribbon pinned to her jacket and a sticker on her back reading: "The state department of the USA doesn't pay me, I pay taxes in the Russian Federation."

She said: "I'm for honest elections, for a lawful state. I want politics to be polyphony, not monotone. It's the cynicism and the silliness of the ruling power that I can't stand any more."

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