Amnesty International said Wednesday that it no longer recognises jailed Russian opposition leader Alexei Navalny as a prisoner of conscience because of past "advocacy of hatred" comments but vowed to still push for his release.

Navalny's arrest at a Moscow airport in January sparked widespread condemnation from rights groups in Russia and abroad as well as from Western leaders who are expected to impose sanctions on Moscow in response.

But Amnesty said it took the decision to rescind his status of prisoner of conscience "in relation to comments he made in the past." 

The London-based activist group did not cite any specific remarks made by Navalny, but he triggered criticism with anti-immigrant statements at the beginning of his political career more than a decade ago.

"Some of these comments, which Navalny has not publicly denounced, reach the threshold of advocacy of hatred, and this is at odds with Amnesty's definition of a prisoner of conscience," it said. 

Amnesty added however that it would continue to demand Navalny's release.

"Navalny has not, to the best of our knowledge, made similar pronouncements in recent years and this decision does not change our resolve to fight for his immediate release," Amnesty said.

It added that the group last week delivered 200,000 signatures to the Russian authorities demanding Navalny's immediate release.

The opposition leader's team responded to Amnesty's decision by accusing the group of having caved to a pressure campaign waged by a columnist associated with Russian state media. 

Navalny's right-hand man Leonid Volkov wrote on Twitter that Amnesty, with the decision, had announced it "was fed crap and we liked it," while key aide Ivan Zhdanov tweeted that the decision was "extremely shameful".

The 44-year-old Kremlin critic was detained after spending months in Germany recovering from a poisoning attack and was then handed a nearly three-year prison term in February for violating parole terms while abroad for medical treatment.

Navalny has emerged in recent years as Russia's leading critic of President Vladimir Putin by publishing investigations into corruption and leading street protests.