However, shortly after May's speech, a spokesperson for Corbyn told publications including Business Insider that the Labour leader did not believe there was sufficient proof to conclude that Russian Federation carried out the poisoning, suggesting that British intelligence services could be wrong.
It was all a throwback to those 1980s days when Mr Corbyn was an awkward squad backbencher.
"When the moment comes to take a stand against, I'm afraid to say, a malign power like Russian Federation, you don't want the Leader of the Opposition popping up and questioning the Government's evidence".
The beleaguered Labour leader was criticised by his shadow defence secretary Nia Griffith as Labour MPs lined up to condemn him for failing to back Theresa May.
Asked directly whether Corbyn believed Russian Federation is responsible for the attack, he said: "I think clearly, as I said, it's important to follow the evidence and to be guided by the evidence".
Asked if Jeremy Corbyn had undermined United Kingdom security assessments that it was "highly likely" Russian Federation was behind their poisoning, Ms Griffith said: "Looking back, perhaps it would have been easier for us if he had made it clear at the beginning of what he said, just how much we support the expulsion of the diplomats".
"If we are to persuade any other nation to take significant measures alongside us, they may ask for a higher burden of proof", she said.
For Labour, the contributions from the backbenches heralded a revolution - a rebellion against the Labour front bench before our very eyes.
The United States and other allies have united behind the U.K. government in blaming Russian Federation for the nerve-agent poisoning of former spy Sergei Skripal and his daughter Yulia.
Corbyn is also facing a call to sack his official spokesperson Seumas Milne after he told reporters there was not yet proof that Russian Federation was responsible for the poisoning, and warned that the intelligence agencies could be wrong as they had in the past with weapons of mass destruction.
Owen Smith, who once challenged MR Corbyn for the leadership but was later taken into the Shadow Cabinet, tweeted his support for an editorial in The Guardian.
"It was absolutely freakish that at a time when you had a blatant use of a Russian nerve agent by the Russians on the streets of Salisbury, he didn't find it in his heart to condemn them".
Teen killed, woman injured in second Austin explosion
He gave few details about the explosives, beyond saying the boxes were an "average size letter box" and "not particularly large". Austin resident Trey Mathis said he expected a package to be delivered Monday but was still nervous when it showed up.
What has Mr Corbyn said since?
Mr Milne said Britain and its North Atlantic Treaty Organisation allies were guilty of "anti-Russian incitement", which was a "dangerous folly", echoing his boss - who has repeatedly criticised Nato's role over Russia.
"Clearly we accept those alternatives are the ones most overwhelmingly likely".
'There can and should be the basis for a common political response to this crime.
Though many have defended the Labour leader's position of following global law and maintaining a dialogue with Russian Federation. And for that reason I think it's very important that we support the action the prime minister laid out on Wednesday as a response to this unprovoked attack'.
"That means when chemical weapons are used, we need more than words, but deeds".
Ms Griffith's comments were quickly supported by several Labour MPs.
His stance on Russian Federation has put them in conflict once again, and this morning, 33 had signed a parliamentary motion blaming Russian Federation "unequivocally" for the attack.
The motion was swiftly signed by a number of prominent critics of Mr Corbyn, some of whom went public with their criticism of the leader's senior spokesman Mr Milne.
One signatory, the former frontbencher Chuka Umunna said: "Mr Milne's comments do not represent the views of the majority of our voters, members or MPs".
Asked whether Corbyn was concerned that his backbenchers felt differently about Russia's culpability, he replied: "In these kinds of cases, there are often initial reactions which aren't later backed up by reality or facts".
"He has been proved to make the right call time and again, over the last 15 to 20 years in particular, when many others made the wrong calls and some of those calls had disastrous consequences".