Britain has accused Russia of creating “fantasies” around the nerve agent attack in Salisbury as the broadcasting watchdog investigates its state broadcaster over impartiality.

Ofcom has opened seven probes into news and current affairs shows including two hosted by former MP George Galloway on Russia Today (RT), which is owned by state media arm TV Novosti.

A spokesperson for the watchdog said: “Until recently, TV Novosti’s overall compliance record has not been materially out of line with other broadcasters.

“However, since the events in Salisbury, we have observed a significant increase in the number of programmes on the RT service that warrant investigation as potential breaches of the Ofcom Broadcasting Code.”

The announcement came as the UK accused Russia of proposing “contradictory and changing fantasies” to deny involvement in the attack on former double agent Sergei Skripal.

Peter Wilson, Britain’s permanent representative to the Organisation for the Prohibition of Chemical Weapons (OPCW), told a meeting of the body’s executive council a “brazen disinformation campaign” was underway.

“They have sought to confuse, distract and brazenly misrepresent facts, despite the thorough, independent OPCW report” that confirmed novichok nerve agent was used, he said.

“To date, Russia has proposed more than 30 contradictory and changing fantasies to explain the Salisbury attack. Russia’s actions to confuse and distract have not worked, but instead show how hard they are working to hide the truth.”

Salisbury poisoning: Yulia Skripal discharged from hospital

Ofcom’s code states that all news must be reported “with due accuracy and presented with due impartiality”, and that “undue prominence” must not be given to a particular side on matters of controversy.

Ofcom said it would announce the outcome of investigations as soon as possible and consider all relevant new evidence alongside RT’s future conduct.

RT has an average audience of 3,400 viewers at any given point during the day and an average weekly reach of 1 per cent of UK adults, according to Ofcom figures.

Owner TV Novosti has been disciplined for 15 breaches of the broadcasting code since 2012, which Ofcom said was not an unusually high number, but most related to Russia’s foreign policy in programmes on the wars in Libya, Syria and Ukraine.

All programmes being currently considered were broadcast after Mr Skripal and his daughter Yulia were poisoned with a nerve agent in Salisbury on 4 March.

They include editions of the Sputnik programme, which is presented by Mr Galloway and his wife Gayatri and claims to “go behind the stories which made the news” with “authoritative and influential” guests.

The two shows in question both discussed the Salisbury attack were broadcast on 17 March, featuring an “independent researcher”, and 7 April, which included Russian commentator Alexander Nekrassov.

Two RT news broadcasts on 18 and 30 March are also being investigated over due impartiality, alongside two editions of the flagship programme Crosstalk, which discussed alleged chemical weapons attacks in Syria on 13 and 16 April, and Worlds Apart with Oksana Boyko on 1 April, which featured an interview with the father of murdered former Russian spy Alexander Litvinenko.

Ofcom noted that several state-funded outlets operate in the UK, including Qatar’s Al Jazeera network and the BBC itself, but said it did not consider actions outside of broadcasting when ruling on licences in order to protect diversity and freedom of expression.

Skripal attack aftermath – in pictures Show all 15 1 /15 Skripal attack aftermath – in pictures Skripal attack aftermath – in pictures Scene of attack Members of the emergency services in hazard suits fix the tent over the bench where Sergei and Yulia Skripal were found unconscious on a park bench in Salisbury in March 2018. Getty Skripal attack aftermath – in pictures Victim - Sergei Skripal The retired Russian colonel and former double agent for MI6 was in a critical condition in hospital for more than two months after being exposed to novichok in Salisbury. He was given refuge in the UK after being jailed in Moscow for treason. Mr Skripal came to Britain as part of a high-profile “spy swap” in 2010 in which four men were exchanged for ten Russian "sleeper agents" in the US. In this image he is speaking to his lawyer from behind bars in Moscow in 2006. AP Skripal attack aftermath – in pictures Victim - Yulia Skripal Yulia Skripal was struck down by a novichok poison alongside her father Sergei. Facebook Skripal attack aftermath – in pictures Scene of attack A police officer stands guard outside a branch of the Italian chain restaurant Zizzi where the pair dined at before falling ill. It was boarded off whilst investigators worked on the building and later found traces of the chemical weapon within it. AFP/Getty Skripal attack aftermath – in pictures Scene of attack Large areas of central Salisbury were cordoned off by police following the discovery of the Skripals. Traces of nerve agent were also found in The Mill pub. PA Skripal attack aftermath – in pictures Victim - Nick Bailey Detective Sergeant Nick Bailey, rushed to the aid of the Russian ex-spy and his daughter who were targeted with a nerve agent. He was hospitalized after aiding them and didn't leave until three weeks after the attack. Wiltshire Police/Rex Skripal attack aftermath – in pictures Police investigation - Skripal’s home Police believe they were poisoned at home, and detectives found the highest concentration of novichok on the front door of Mr Skripal’s house. Getty Skripal attack aftermath – in pictures Theresa May visits scene of attack Britain's Prime Minister Theresa May spokes with Wiltshire Police's Chief Constable Kier Pritchard near where the Skripal's were found. Britain expelled 23 Russian diplomats over the nerve agent poisoning and suspended high-level contacts, including for the World Cup on March 14. Theresa May told parliament that Russia had failed to respond to her demand for an explanation on how a Soviet-designed chemical, Novichok, was used in Salisbury. AFP/Getty Skripal attack aftermath – in pictures Skripal days before attack Sergei Skripal days before he was exposed to Novichok, that has left him fighting for life. ITV News Skripal attack aftermath – in pictures Police investigation - military involvement British soldiers were deployed soon after the attack to help a counter-terrorism investigation into the nerve agent attack. One of the places they were asked to help out with was Skripal's home and it's surrounding. They were asked to remove a vehicle connected to the agent attack in Salisbury, from a residential street in Gillingham. AFP/Getty Skripal attack aftermath – in pictures Police investigation Personnel in protective coveralls and breathing equipment cover an ambulance with a tarpaulin at the Salisbury District Hospital. AFP/Getty Skripal attack aftermath – in pictures Police investigation The investigation extended to the grave of Sergei Skripal's son Alexander in London Road cemetery. Getty Skripal attack aftermath – in pictures Police investigation The Counter Terrorism Policing Network requested assistance from the military to remove a number of vehicles and objects from Salisbury. EPA Skripal attack aftermath – in pictures Home Secretary visits scene of attack Home Secretary Amber Rudd visited the scene of the nerve agent attack at the Maltings shopping centre on 9 March. Getty Skripal attack aftermath – in pictures Yulia Skripal speaks for the first time Yulia Skripal, speaking for the first time, said she felt lucky to have survived the nerve agent attack in Salisbury which left her fighting for life. Ms Skripal said her life had been “turned upside down” by the assassination attempt. But the Russian national added she hoped to return to her homeland one day, despite the Kremlin being blamed for the attack. Reuters

“States sometimes commit, or will have committed, acts which are contrary to UK and generally accepted values,” a spokesperson said.

“In our judgment, it would be inappropriate for Ofcom always to place decisive weight on such matters in determining whether state-funded broadcasters were fit and proper to hold broadcast licences.”

Ofcom stressed that it was not seeking to pass judgement on the attack in Salisbury itself, which the government has attributed to Russia despite Kremlin denials.

“We disagree with the position taken by Ofcom; our broadcasting has in no way changed this week from any other week, and continues to adhere to all standards,” a spokesperson for RT said.

“By linking RT to unrelated matters, Ofcom is conflating its role as a broadcasting regulator with matters of state. RT remains a valuable voice in the UK news landscape, covering vital yet neglected stories and voices, including those of the many MPs and other UK public figures who have been shut out of public discourse by the mainstream media.”

Mr Galloway has not yet responded to The Independent’s request for comment.

Britain and its allies have expelled Russian diplomats over the Salisbury incident, which sparked an escalating diplomatic row that heightened further following an alleged chemical attack in Syria and airstrikes against Bashar al-Assad’s forces.

On Tuesday, officials announced the start of decontamination work in Salisbury at nine sites including Mr Skripal’s house, the restaurant and pub he visited with his daughter and areas used by emergency services.

The operation will involve around 200 military personnel and is expected to take several months.