Vladimir Putin has sharply criticised former Russian spy Sergei Skripal, calling him a 'scumbag'.

Mr Skripal and his daughter Yulia were found slumped on a park bench in Salisbury in March, with officials later saying the pair had been poisoned by the nerve agent novichok.

The British government and several of its allies have accused Russia of being behind the attack - accusations Moscow has repeatedly denied.

Speaking at an energy conference in Moscow today, the Russian president directly attacked Mr Skripal - calling him a 'traitor'.

He said: "I see that [media outlets] are pushing the theory that Mr Skripal was almost some kind of human rights activist.

"He was simply a spy. A traitor to the motherland. There is such a concept - a traitor to the motherland. He was one of those. He's simply a scumbag, that's all."

Mr Putin added: "He was caught, he was punished, he spent five years in prison, we let him go, he left and continued cooperating with, providing consultations to (foreign) security services."

67-year-old Sergei Skripal was a former colonel within Russian military intelligence who served as a double agent for UK intelligence services.

He was convicted of treason in Russia and jailed, but was sent to Britain as part of a spy swap in 2010.

Both he and his daughter have been discharged from hospital following the attack earlier this year, although Mr Skripal has yet to speak publicly.

Last month, police in the UK named two Russian nationals - suspected Russian intelligence officers - they believed to be behind the attack.

Their names were given as Alexander Petrov and Ruslan Boshirov, although UK officials have suggested the men used aliases to travel to England.

The two suspects subsequently appeared in an interview on Russian state television, claiming they had nothing to do with the Salisbury poisoning.

Last week, an investigative journalism website claimed to have identified one of the men as a Russian military intelligence agent.