This article is more than 2 years old

This article is more than 2 years old

Jeremy Corbyn’s reaction to the prime minister’s Russia statement has sparked a Labour party row, as his spokesman questioned the evidence that Moscow was behind the Salisbury attack.

The Labour leader came in for sustained criticism, including from his own MPs, after he failed to condemn the Kremlin directly for carrying out the poisoning of former Russian spy Sergei Skripal and his daughter, Yulia.

Corbyn called the incident “an appalling act of violence”, saying on Wednesday: “Nerve agents are abominable if used in any war. It is utterly reckless to use them in a civilian environment.”

But he left open the possibility – as Theresa May did on Monday – that the nerve agent could have been used by someone else other than the Russian state.

His comments brought shouts of “shame” from the Conservative benches.

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The row later intensified when Corbyn’s spokesman appeared to compare the evidence for direct Russian involvement, with the shaky case for war in Iraq.

Briefing journalists as the debate continued in the Commons, he said: “I think obviously the government has access to information and intelligence on this matter which others don’t; however, also there’s a history in relation to WMD and intelligence which is problematic to put it mildly.

“So I think the right approach is to seek the evidence; to follow international treaties, particularly in relation to prohibited chemical weapons, because this was a chemical weapons attack, carried out on British soil. There are procedures that need to be followed in relation to that.”

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He highlighted an alternative possibility raised by May on Monday: that the Russian state could have lost control of supplies of the nerve agent.

“In relation to the second alternative explanation, in other words the loss of control of military-grade nerve agent, we highlighted today and we have done repeatedly, the dangers of mafia-like groups and oligarchic interests in London, and their links with elements within the Russian state, and that we need to take more firm action on that.”

With the briefing still continuing, his remarks about the use of intelligence were relayed back to the chamber by the Tory MP Alec Shelbrooke, who asked May about them.

The prime minister said she was “surprised and shocked by the spokesman for the leader of the opposition”.

As disquiet grew among Labour MPs at Westminster, several, including Chuka Umunna, Anna Turley and Mike Gapes, took to Twitter to criticise Corbyn’s spokesman, the former Guardian columnist Seumas Milne, by name. Turley said: “I’m afraid Seumas doesn’t speak for my Labour, or British values.”

Chuka Umunna (@ChukaUmunna) Have read the comments of the Leader of the Opposition’s spokesperson. Mr Milne’s comments do not represent the views of the majority of our voters, members or MPs. We’ll get abuse for saying so but where British lives have been put at risk it is important to be clear about this.

Another Labour backbencher, who did not wish to be named, said: “Putin’s constant and shameful apologist might just as well stand aside and let the Russian ambassador write the speeches and brief the media himself.”

Labour is deeply divided over foreign policy, and some backbenchers fear the leadership is too sympathetic to Russia; but Corbyn’s spokesman insisted the Labour leader had repeatedly made the right judgments about foreign policy issues in the past.

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In the Commons, Corbyn stressed the need to gather evidence and abide by international law, underlining the role of the Organisation for the Prohibition of Chemical Weapons (OPCW), based in The Hague.

He said: “If the government believes that it is still a possibility that Russia negligently lost control of a military-grade nerve agent, what action is being taken through the OPCW with our allies?”

Corbyn then asked: “How has she responded to the Russian government’s request for a sample of the agent used in the Salisbury attack, to run its own tests?”

May attacked Corbyn, saying the Russians had already been given the chance to explain where the nerve agent had come from and that the government had sought consensus.

“I am only sorry that the consensus does not go as far as the right honourable gentleman, who could have taken the opportunity as the UK government has done to condemn the culpability of the Russian state,” she said.

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A string of Labour backbenchers, including Yvette Cooper, Ben Bradshaw and Hilary Benn, then intervened to offer their backing to May, in what appeared to be pointed responses to Corbyn’s stance.

Cooper, the chair of the home affairs select committee, was greeted with loud cheers when she said Russian state involvement, as the UK government has concluded, “should be met with unequivocal condemnation”.

May thanked Cooper and, in another remark aimed at Corbyn, said: “I know it is representative of many of her friends on the backbenches opposite.”

Bradshaw, a former cabinet minister, said: “Can I assure the prime minister that most of us on these benches fully support the measures that she has announced, and indeed some of us think they could have come a bit sooner.”

Another Labour MP, Chris Bryant, said he completely supported everything the prime minister had said and that Putin’s Russia was “keeping his people poor and kills its political opponents”.

Sammy Wilson of the Democratic Unionist party described Corbyn’s cautious stance as “appeasement”.

Several Labour MPs, including John Woodcock, Alison McGovern and Wes Streeting, later signed an early day motion – effectively a petition laid before parliament – the text of which said: “This house unequivocally accepts the Russian state’s culpability for the poisoning of Yulia and Sergey Skripal.”