Russia's government is using an extremism trial to put an end to the movement surrounding the opposition figure Alexei Navalny.

A team of medics including Alexei Navalny's personal doctor, Anastasia Vasilyeva, are denied access to a penal colony hospital where the Russian opposition figure is being treated. Navalny, 44, launched a hunger strike on March 31 and his medical team has warned that his health is failing rapidly.

The NGO's chief "knows that Navalny is facing prison conditions that amount to torture, including through sleep deprivation." She said Amnesty's recent removal of his "prisoner of conscience" status would be reviewed.

Supporters of opposition leader Alexei Navalny have called for half a million Russians to take to the streets. Observers say that's a tall order.

Kremlin critic Alexei Navalny is serving his two and a half years sentence for violating parole at penal colony no.2 in the provincial town of Pokrov, 100 kilometres east of Moscow. It is part of a sprawling network of some 684 work colonies that today holds some 393,000 prisoners. The system requires inmates to carry out menial labour for a meagre salary and is routinely flagged by Russian advocacy groups for imposing long working hours and overlooking harsh conditions.

The rights group said Navalny's past "advocacy of hatred" was the reason behind its decision. His supporters accused Amnesty of having caved to a pressure campaign.

Calls are growing from the international community for jailed Kremlin critic Alexei Navalny to be freed. Moscow has hit back, saying other countries should not interfere in Russia's internal matters.

A Moscow court jails the Kremlin's most prominent critic Alexei Navalny for nearly three years, triggering more protests resulting in more than a thousand arrests.

Meanwhile, an ally of Alexei Navalny has called for new protests across Russia to demand the release of the jailed dissident. And the Kremlin has accused US tech companies of interfering in Moscow's internal affairs.

Russian opposition leader Alexei Navalny says he is facing a "mockery of justice" as police in Moscow organised a makeshift hearing in a police station a day after his dramatic airport arrest.

Kremlin critic Alexei Navalny urges Russians to stage mass anti-government protests during a court hearing after his arrest on arrival in Moscow from Germany.

Russia's prison service has asked Alexei Navalny to report to its office in Moscow in one day, failing which he could face jail. Navalny said the statement means the state "officially" recognizes his August poisoning.