Foreign Affairs Minister Chrystia Freeland says her department is following with “very close interest” the possible poisoning of a Russian-Canadian anti-Kremlin activist who is currently recovering in Germany.

Pyotr Verzilov – a well-known member of Russian punk rock group Pussy Riot, which has regularly protested against Vladimir Putin’s government – fell ill after he attended a friend’s court hearing in Moscow last week. He was rushed to hospital with symptoms including disorientation, vision loss, difficulty speaking, and mobility problems.

On the weekend, Verzilov was transferred via private medevac to Berlin’s Charite hospital for further treatment. Dr. Kai-Uwe Eckardt, the head of the hospital’s intensive care unit, told reporters that the activist is receiving care there, but he’s not in life-threatening condition.

Eckardt also said that it was “highly plausible” a poisoning took place and Verzilov’s medical team has discovered “no evidence whatsoever that there would be another explanation for his condition.”

Eckardt would not speculate on how the possible poisoning might have occurred or who was responsible for it.

During a media scrum on Tuesday outside the House of Commons, Freeland said that she was “personally very closely engaged in” Verzilov’s case.

“I was very glad to have the opportunity to speak with his mother Elena on Friday,” she said. "He is a Canadian citizen and we have assured his family that Canada is here to support him and we are working very closely with him, with his family.”

Freeland said that Canadian officials have been in contact with the Verzilov family along with German officials “with whom we have a very good relationship.”

The foreign affairs minister did not comment on the possibility of Verzilov having been poisoned – saying only that the government is monitoring the situation and will “act appropriately.”

Verzilov’s mother told CNN on Tuesday that his family is “optimistic” he will make a full recovery and they’re taking it day-by-day. She said they haven’t told him that he may have been poisoned because he’s currently focused on relearning simple tasks and recovering.

“I think he just needs time for recovering,” she said. “We’re just optimistic about it. I hope he will be OK.”

The German doctors said Verzilov’s symptoms indicate that he’s suffering from an anticholinergic syndrome that can result in a disruption of the nervous system responsible for regulating inner organs. They said they don’t know what substance or substances may be behind the poisoning and that it could have been the result of high doses of certain pharmaceuticals or plants containing toxins.

Veronika Nikolshina, Verzilov’s partner, said it took a few hours before they realized how serious his condition was and that he required medical attention.

“It was really shocking. I was really surprised when it started to be worse and worse from hour to hour,” she told CNN.

Verzilov is expected to make a full recovery with hopefully no permanent damage, Eckardt said. The Russian-Canadian activist has already been communicating with staff at the hospital, but they haven’t been able to question him about his medical history as of yet.

Pussy Riot has a long history of protesting against Putin and his government’s excessive use of force. In July, Verzilov and his fellow bandmates served 15-day jail sentences for disrupting the FIFA World Cup’s final by running onto the field.

Nadezhda Tolokonnikova, another member of the band, told reporters on Tuesday that she expects Verzilov will return to Moscow after he recovers.

With files from The Associated Press