A Moscow court has ordered Russian protest leader Alexei Navalny to be placed under house arrest, honouring a request from investigators probing an alleged embezzlement case.

Navalny, who last year was given a suspended five year sentence in a separate timber embezzlement case, faces charges in this case along with his brother Oleg of stealing and laundering a total of 51 million rubles ($1.4m) from cosmetics company Yves Rocher and a Russian firm.

Navalny, known for his virulent criticism of President Vladimir Putin, has previously dismissed the allegations of theft as "weird" and baseless.

The State Investigative Committee has in the past accused Navalny of organising a scheme to steal assets - estimated to be worth about $500,000 - from a state timber company.

The 36-year-old anti-corruption crusader has been instrumental in rallying Russia's young internet generation against the rule of President Vladimir Putin.

Navalny, a lawyer, has also led a series of rallies in Moscow, drawing tens of thousands of people opposed to Putin’s policies.

After being defeated as Moscow mayoral candidate last year, Navalny launched hundreds of lawsuits contesting the victory of his rival, Sergei Sobyanin.

Navalny delivered boxes full of complaints of fraud to Moscow city court, and began filing 951 lawsuits with 36 district courts.