RUSSIAN President Vladimir Putin has called Sergei Skripal, the ex-spy who was poisoned with a military grade nerve agent in Britain, a traitor and a "scumbag".

It was the first time Putin has directly condemned Skripal, who spent weeks in hospital with his daughter Yulia after both were poisoned in the city of Salisbury in March.

The UK Government put the blame squarely on Russia but Moscow has denied any role in the incident.

Asked about sanctions on Russia triggered by the attack, Putin called the ex-spy "just a scumbag" who betrayed his country.

He reiterated Russia's claim that it has nothing to do with the poisoning.

Putin said the former agent was of no interest to the Kremlin since he was tried in Russia and exchanged in a spy swap in 2010.