Senior Labour figures have played down suggestions the party is divided over Russia.

Jeremy Corbyn’s warning not to “rush ahead of the evidence” over the nerve agent attack in Salisbury received a lukewarm response from a number of his backbenchers — who signed a motion which “unequivocally” accepted the Russian state’s “culpability”.

Shadow chancellor John McDonnell said that Mr Corbyn’s message had been “misread”, and that Labour agreed with Theresa May that Russia was responsible for the attack.

Speaking to Peston on Sunday, he said: “The Prime Minister is right, whatever they say Russia’s to blame so now we’ve got to build, exactly as she is doing the international coalition that takes effective action.”

He added: “There’s a pattern of people being murdered here, therefore it leads you to the conclusion that [Vladimir] Putin has questions to answer because this is highly likely this could have been a state execution.”

Mr McDonnell called for the introduction of an “oligarch levy” to strengthen the UK’s hand in imposing effective sanctions on Russia.

The levy would see a charge introduced against purchases of residential property by offshore trusts located in known tax havens — raising an estimated £875 million a year, according to Labour.

Mr McDonnell, reacting to reports of Labour divisions over Mr Corbyn’s response to Russia, said the Labour leader had given a “constructive critique” and others “had misread that”.

He said: “It’s the role of a responsible opposition to ensure that they have an honest critique of the Government and what they’re doing.

“Support them when they’re right, that’s what Jeremy did, he said I support and condemn these actions, supported the Prime Minister on her conclusions.”

He added: “It is a constructive critique, I think others have misread that.”

Shadow attorney general Shami Chakrabarti also presented a united front when she appeared on BBC One’s Andrew Marr Show.

She said: “I am here to make clear that I am completely at one, not just with Jeremy but with Nia Griffith, Emily Thornberry, Keir Starmer.

“We must condemn Russian responsibility, whether it is negligent or whether it is even more serious.”

Labour MP Yvette Cooper dismissed suggestions some colleagues were considering setting up a new party because they were unhappy with Mr Corbyn’s response.

She told BBC One’s Sunday Politics: “I think this is a load of rubbish. Certainly I would have no truck with it even if it wasn’t a load of rubbish, but I have not heard this.”