MOSCOW: More than 20,000 people packed a Moscow square Saturday to protest the authorities' refusal to allow opposition candidates to register for local polls.

Joined by opposition leaders such as Alexei Navalny, protesters gathered in the capital after authorities refused to register independent politicians seeking to contest the September vote for the capital's parliament.

The crowd chanted: "This is my city!"

White Counter, an NGO that tracks participation in protest rallies, said about 21,500 people took part in Saturday's rally.

"We will show them this is a dangerous game," Navalny bellowed from a stage set up on the protest square.

"We should fight for our candidates," he said as the huge crowed cheered and waved Russian flags.

The 43-year-old threatened an even bigger rally next week, near the mayor's office, unless Moscow's electoral authorities register a new crop of popular politicians including Ilya Yashin, Lyubov Sobol and Dmitry Gudkov for the vote within seven days.

"We will not give up!" added Navalny ally Sobol, who has been on a hunger strike for a week to protest the authorities' refusal to allow her to run.

"I am sure that we will win," said the 31-year-old lawyer, propped up by an ally on stage.

Fellow opposition contender Gudkov accused the authorities of stealing not only people's money and votes but their very future.

"We've been living in an occupied country for the past 20 years," the former lawmaker said.

Opposition candidates fought tooth and nail to get on the ballot paper as they seek to capitalise on popular discontent with the Russian authorities, falling approval ratings for Putin, and anger over declining living standards and unchecked corruption.

- We are not 'dead souls' -

They were made to jump through countless hoops, with each having to collect 5,000 signatures from supporters to be eligible.

Electoral authorities this week still refused to register a number of the would-be candidates, accusing them of faking some of the signatures.

Critics said some of the officials' reasoning bordered on the absurd.

The Kremlin dismissed the opposition's complaints, but many Russians are furious at what they perceive as electoral interference.

Greg Yudin, a lecturer at the Higher School of Economics, who supported an independent candidate but whose signature was not recognised, said he was surprised to discover -- along with thousands of other Muscovites -- that he apparently did not exist.

"All of us are ghosts. We are the nobodies," he said on Facebook.

Political observer Kirill Rogov said the independent candidates' exclusion was "one of the largest frauds in Russia's electoral history".

"We are witnessing a major large-scale crime," he wrote on his blog.

Some 7.2 million Muscovites are eligible to elect 45 lawmakers to the local parliament, currently dominated by the United Russia ruling party. —AFP