The opposition leader’s lawyer has said the activist has a fever, a cough, and has lost weight
The 44-year-old is a fierce critic of Russian president, Vladimir Putin.
It is understood Navalny will be tested for Covid-19 after showing symptoms of a “respiratory illness”, with his lawyer describing him as “seriously ill.”
Navalny went on hunger strike last week, claiming prison staff were refusing to treat him for severe back pain and neurological symptoms in his legs.
“I’ve declared a hunger strike with the demand that the law be enforced and a doctor be admitted to see me,” Navalny wrote in a note shared on social media.
“So for now I lie hungry, but for the time being with two legs.”
This is the latest chapter in Navalny’s relationship with the Russian state, after he collapsed on a flight in August 2020 after being poisoned with the nerve agent Novichok.
An investigation found a group of operatives, directed by the most senior in the Kremlin, orchestrated the poisoning in Siberia; Novichok was used in the Sailsbury poisonings in 2018, which were also organised by the Russian government.
The opposition leader has claimed Putin himself was responsible for organising the attack, and in September 2020 he wrote in his blog: “I know who tried to kill me.
“We know the names, we know the job ranks, and we have the photos.”
The Kremlin have consistently rejected claims that they are responsible for the poisoning, however the Russian president said government agents were following Navalny on his trip but added if they’d wanted to kill him, they’d “have finished the job.”
Navalny was treated in Berlin, Germany after the poisoning before dramatically returning to Russia in January 2021, where he was immediately detained.
His detention triggered protests across Russia and international condemnation, with protestors taking to the street in sub-zero temperatures to demand his release.
The US then president-elect Joe Biden’s national security advisor said: “The Kremlin’s attacks on Mr Navalny are not just a violation of human rights, but an affront to the Russian people who want their voices heard.”
The Russian authorities claim Navalny has been detained for violating conditions imposed after being convicted for embezzlement.
Meanwhile, a separate case has been launched against the activist on fraud charges.
Navalny claims these are politically motivated.
He has been sentenced to two and a half years at Pokrov correctional colony, 60 miles outside of Moscow; the colony is known to be particularly punitive.
Navalny has previously accused guards of torturing him with sleep deprivation and encouraging other inmates to harass him.
