Russian Prime Minister Dmitry Medvedev has dismissed allegations of corruption that sparked nationwide protests drawing hundreds of thousands of people.

The allegations were levelled by outspoken Kremlin critic Alexei Navalny, who documented Medvedev's expansive property holdings and lavish lifestyle through his investigative reporting outlet known as the Anti-Corruption Foundation.

Navalny plans to challenge Russian President Vladimir Putin at next year's elections, vowing to clean up Moscow. However, Medvedev has now claimed that Navalny's assertions are "malarkey".

"This character openly says that 'Everyone is horrible, choose me for president'," Medvedev said in televised remarks on Wednesday (5 April), according to AFP.

"For that he drags people out to the streets, often minors, which is practically a crime, making them hostages of his political programme."

Navalny first called the protests on 26 March after his YouTube video detailing the alleged corruption claims was watched more than 10 million times – a figure that has since risen to over 17 million.

However, Russian police immediately branded the protest illegal and arrested over 1,000 demonstrators, including Navalny.

He was sentenced to 15 days in prison and will remain behind bars until next week.

Dark side to Navalny?

Though Navalny has been lauded in the West as a saviour of Russia and a palatable option to replace Putin, there are more troubled sides to his personality.

"The fact that Navalny is a vocal Kremlin critic and ardent opponent of Vladimir Putin has ensured that he has become somewhat of a media darling in the West," Danielle Ryan wrote for Salon.

"He is sometimes hailed as a hero in Western coverage. Time magazine once called him 'Russia's Erin Brockovich'.

"What is reported less often about Navalny are his nationalist leanings, ties to neo-Nazi groups, xenophobic comments and extreme anti-immigrant views.

"References to Navalny's nationalism in the West are usually ​buried or brushed off​, while the headlines sing his praises.

"While we seem somewhat better able to appreciate the complexities of politics and political figures in our own nation, we tend to regard Russia in very simplified terms; there's a 'bad guy' in power and we must therefore support the valiant and oppressed 'good guy'."

Anti-Corruption Fund's revelations regarding Russian Prime Minister Dmitry Medvedev (with English subtitles).