A prominent MP has accused the BBC of being “useful idiots” for Russia, for inviting the host of a Kremlin-backed television channel to speak on the corporation’s flagship political programme.

The appearance of Afshin Rattansi, a presenter on the channel formerly known as Russia Today, now called RT, came after Theresa May said it was “highly likely” Russia was behind the poisoning of a double agent and his daughter in Salisbury. 

It prompted Conservative MP Sarah Wollaston to write on Twitter: “Seriously, why is BBC Question Time giving a platform to RT, a mouthpiece for Putin? 

“Russia has unleashed a nerve agent here in Britain & three people, including a police officer, have been fighting for their lives. Hope other panelists walk out in disgust.” 

Conservative columnist Tim Montgomerie was similarly perturbed by the BBC “giving big platforms to such one-eyed propagandists”.

And radio host Ian Dale said:

“I interviewed this unpleasant piece of work Afshin Rattansi once. I asked my producer never to book him again. Or indeed anyone else from RT. BBC Question Time should be embarrassed to have him on their panel.”

As soon as Rattansi was invited to speak during the programme, he hit out at Sarah Wollaston and suggested the Totnes MP was attacking free speech.

Rattansi said: “Thank you for inviting me because the head of the liaison committee in Parliament, Sarah Wollaston MP … has told all these people on the panel to walk off the minute I sit here. That’s free speech in this country.”

Labour’s Sir Keir Starmer, on the panel, hit back: “She hasn’t had any discussion with me whatsoever.”

Rattansi replied: “It’s on Twitter.”

Prompting applause, the Shadow Brexit Secretary replied: “I don’t care what she’s tweeted. I know she’s not spoken to me.”

Rattansi then made clear he “did not have that certainty” over whether the Russian state was responsible for the poisoning, adding: “We cannot believe our governments any more the way we used to, just because a Prime Minister stands up and says the security services have told us something. Those days are gone.”

His comment prompted another online response from Wollaston. “BBC Question Time become the useful idiots allowing the peddling of the RT line with almost zero challenge,” she wrote. 

“Useful idiot” is a pejorative term for an unwitting propagandist.

Viewers also found Rattansi’s appearance divisive.

Earlier this week, Ofcom said it would consider whether RT should broadcast in the UK if Russian involvement is proven in the Salisbury nerve agent attack.

The regulator said it had written to RT on Tuesday to explain that evidence of unlawful state interference would affect whether it was deemed “fit and proper” to hold a broadcasting licence.

MPs had voiced concern about the Russian news channel in the House of Commons, following a statement by Mrs May on the spy poisoning.

Labour former minister Chris Bryant said: “Can we just stop Russia Today just broadcasting its propaganda in this country?”