Alexei Navalny
Russian opposition leader Alexei Navalny and his wife Yulia are seen at the passport control point at Moscow's Sheremetyevo airport on January 17, 2021. Image Credit: AFP

Russian police detained opposition leader Alexey Navalny as he arrived in Moscow after being treated in Germany for a poisoning, an arrest that will likely fuel tension with Western nations.

Navalny, 44, was met by officers at passport control as he landed in Moscow on a plane from Berlin on Sunday, according to a live video feed on his YouTube channel. The Federal Penitentiary Service said he had been detained for violating the terms of a suspended sentence, state-run Tass reported.

"This is my home," he told reporters who'd traveled with him. "I'm not scared of anything," he said shortly before he was detained. Navalny boarded knowing that he could face a lengthy prison term if he returned.

He kissed his wife, Yuliya, goodbye before walking off with police. Authorities said he would be held pending a court decision on his sentence.

Dozens of his supporters were detained by police at Moscow's Vnukovo Airport, where he had appealed to them to meet him. The flight was diverted to another airport shortly before arrival.

Navalny, whose anti-corruption exposes and success in galvanizing anti-government votes have increasingly needled the authorities, had been recovering in Germany from a nerve-agent attack.