Former chess king turned Kremlin critic Garry Kasparov faced the threat of prison on Monday after being questioned over claims that he bit a policeman at the sentencing of the Pussy Riot punk rockers.

The bizarre but serious charge could put the fast-talk 49-year-old behind bars for five years and deliver even graver harm to Moscow's deteriorating relations with the West in President Vladimir Putin's third term.

Kasparov has been a seminal figure of the Russian opposition who has used his global fame to publish articles in the Western press detailing the difficulties human rights encountered during Putin's previous 12 years in power.

Kasparov had defended their "punk prayer" stunt performance as "political speech that should be unconditionally protected" - a view unanimously shared by Western powers.

No charges against Kasparov have yet been filed and he only appeared Monday at a Moscow district police station to give initial testimony. Kasparov dismissed the biting allegations with characteristically bitter irony on his Twitter account.

"I am sorry if the policeman who was beating me on the head had hurt his hand," the man widely regarded as history's greatest chess player tweeted.