Just before the ruling, Navalny, who is the most prominent critic of President Vladimir Putin, had denounced the proceedings as a vain attempt by the Kremlin to scare millions of Russians into submission. His team called on Russians to rally immediately in central Moscow in protest.

The ruling came despite massive protests across Russia over the past two weekends and Western calls to free the 44-year-old anti-corruption campaigner.

The prison sentence stems from a 2014 embezzlement conviction that Navalny has rejected as fabricated and politically motivated.

Navalny was arrested Jan. 17 upon returning from his five-month convalescence in Germany from the attack, which he has blamed on the Kremlin. Russian authorities deny any involvement. Despite tests by several European labs, Russian authorities said they have no proof he was poisoned.

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As the order was read, Navalny smiled and pointed to his wife Yulia in the courtroom and traced the outline of a heart on the glass cage where he was being held. “Everything will be fine,” he told her as guards led him away.

Earlier in the proceedings, Navalny attributed his arrest to Putin’s “fear and hatred,” saying the Russian leader will go down in history as a “poisoner.”

“I have deeply offended him simply by surviving the assassination attempt that he ordered,” he said.

“The aim of that hearing is to scare a great number of people,” Navalny added. “You can’t jail the entire country.”

Russia’s penitentiary service alleges Navalny violated the probation conditions of his suspended sentence from the 2014 conviction. It asked the Simonovsky District Court to turn his 3 1/2-year suspended sentence into one that he must serve in prison, although he has spent about a year of it under house arrest that will now be counted as time served.

Navalny emphasized that the European Court of Human Rights has ruled that his 2014 conviction was unlawful and Russia paid him compensation in line with the ruling.

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Navalny and his lawyers have argued that while he was recovering in Germany from the poisoning, he couldn’t register with Russian authorities in person as required by his probation. Navalny also insisted that his due process rights were crudely violated during his arrest and described his jailing as a travesty of justice.

“I came back to Moscow after I completed the course of treatment,” Navalny said at Tuesday’s hearing. “What else could I have done?”

Navalny’s jailing has triggered massive protests across Russia for the past two weekends, with tens of thousands taking to the streets to demand his release and chant slogans against Putin. Police detained over 5,750 people Sunday, including more than 1,900 in Moscow, the biggest number the nation has seen since Soviet times. Most were released after being handed a court summons, and they face fines or jail terms of seven to 15 days. Several people faced criminal charges over alleged violence against police.

“I am fighting and will keep doing it even though I am now in the hands of people who love to put chemical weapons everywhere and no one would give three kopecks for my life,” Navalny said.

In court, Navalny thanked protesters for their courage and urged other Russians not to fear repression.

“Millions can’t be jailed,” he said. “You have stolen people’s future and you are now trying to scare them. I’m urging all not to be afraid.”

Observers noted that authorities want Navalny in prison, fearing that he could run an efficient campaign against the main Kremlin party, United Russia, in the parliamentary election in September. “If Navalny remains free, he is absolutely capable of burying the Kremlin’s plans regarding the outcome of the Duma election,” said political analyst Abbas Gallyamov.

After his arrest, Navalny’s team released a two-hour YouTube video featuring an opulent Black Sea residence allegedly built for Putin. The video has been viewed over 100 million times, fueling discontent as ordinary Russians struggle with an economic downturn, the coronavirus pandemic and widespread corruption during Putin’s years in office.

Putin insisted last week that neither he nor his relatives own any of the properties mentioned in the video, and his longtime confidant, construction magnate Arkady Rotenberg, claimed that he owns it.

As part of efforts to squelch the protests, the authorities have targeted Navalny’s associates and activists across the country. His brother Oleg, top ally Lyubov Sobol and several others were put under house arrest for two months and face criminal charges of violating coronavirus restrictions.

Also Read: Russian opposition politician Navalny poisoned, hospitalized

The jailing of Navalny and the crackdown on protests have stoked international outrage.

British Foreign Secretary Dominic Raab denounced Tuesday’s ruling.

“The U.K, calls for the immediate and unconditional release of Alexei Navalny and all of the peaceful protesters and journalists arrested over the last two weeks,” Raab said. “Today’s perverse ruling, targeting the victim of a poisoning rather than those responsible, shows Russia is failing to meet the most basic commitments expected of any responsible member of the international community.”

Visiting Moscow earlier Tuesday, Swedish Foreign Minister Ann Linde, the current chair of the Organization for Security and Cooperation in Europe, urged Russia to release Navalny and condemned the crackdown on protests.

EU foreign policy chief Josep Borrell, who will visit Moscow later this week, has criticized the detentions and the disproportionate use of force against protesters, emphasizing that Russia must comply with its international commitments on human rights.

Russia has dismissed U.S. and EU criticism as meddling in its domestic affairs and said Navalny’s current situation is a procedural matter for the court, not an issue for the government.

More than a dozen Western diplomats attended the hearing, and Russian Foreign Ministry spokeswoman Maria Zakharova said their presence was part of efforts by the West to contain Russia, adding that it could be an attempt to exert “psychological pressure” on the judge.

Kremlin spokesman Dmitry Peskov said Russia is ready for dialogue about Navalny, but sternly warned that it wouldn’t take Western criticism into account.

“We are ready to patiently explain everything, but we aren’t going to react to mentor-style statements or take them into account,” Peskov said in a conference call with reporters.