BERLIN — Russian activist Alexei Navalny arrived here on Saturday morning on a plane departing from Siberia after Russian doctors said his condition was stable enough for him to travel.

News agency AP reported he's currently being treated at Berlin's Charite hospital. When he arrived, his condition was "stable", according to the German doctors who flew with him.

The 44-year-old felt unwell on Thursday morning on his way to Moscow and had been hospitalized in the intensive care unit the Siberian town of Omsk ever since.

"The struggle for Alexey's life and health is just beginning, and there is still a lot to go through," his spokeswoman Kira Yarmysh said "but now at least the first step has been taken".

His closest collaborators suspect he might have been poisoned because of his political activity, but doctors at the Omsk hospital said they didn't find poison in Navanly's blood.

He's being taken to Germany by an NGO called Cinema for Peace. The organization brought to Siberia a team of doctors who were briefly allowed to see Navalny on Friday.

Cinema for Peace, which is known for its actions helping human rights defenders in Russia, has already carried out a similar operation when it medevacked Piotr Verzilov, a member of controversial Russian group Pussy Riot, after he was poisoned in 2018.

Navalny's representatives had previously applied to the European Court of Human Rights (ECHR) to allow for his medical evacuation. Yarmysh said that the travel ban represented a direct threat to his life and was decided by the Kremlin.

Friday night, the court ordered that Navalny's family and personal doctors be allowed to visit him and ensure the state of his health. The ECHR also urged transfer to Germany be made as soon possible and said Russia must ensure "without delay" that the ECHR, Navalny's wife and his doctor gain access to his medical files.

Navalny's doctor Vasilyeva had asked for support from the Ministry of Health to gain access to his medical records and transport him to a hospital in Moscow or abroad.

Earlier, Yarmysh had alerted Twitter users on Thursday morning, saying Navalny is in intensive care in a Siberian hospital after apparently being poisoned.

Navalny was on a flight from Siberia to Moscow early on Thursday morning when the plane had to make an emergency landing due to a sudden deterioration of his health, his spokesperson, Yarmysh tweeted. "Alexei has been poisoned, intoxicated," and "is now in intensive care."

Vyacheslav Gimadi, a lawyer with Navalny's foundation, said the team is requesting Russia's Investigative Committee open a criminal probe. “There is no doubt that Navalny was poisoned because of his political stance and activity,” Gimadi said in a tweet on Thursday.

Yarmysh said they suspect a substance was mixed into his tea since it was the only thing he drank that morning. She adds, "doctors say the toxin was absorbed faster through the hot liquid."

As more information about Navalny's condition comes to light, political leaders are apprehensively watching the situation unfold. EU Commission spokesperson Nabila Massrali said the EU expects "a swift, independent and transparent investigation, and if [poisoning] is confirmed those responsible must be held to account".

"We trust that the Russian authorities will stand by their promises to allow Mr Navalny to be safely and speedily transferred abroad, in order to receive medical treatment in line with the wishes of his family."

MEP Guy Verhofstadt wished Navalny a quick recovery on Twitter. Lithuania's Foreign Minister Linas Linkevicius tweeted he was concerned and following the events.

In the US, former presidential candidate Hillary Clinton expressed her support for Navalny's wife and demanded he be allowed to be transported to Germany for treatment. — Euronews