The row began earlier this week, when Corbyn accused Johnson of “misleading” the public by decisively blaming Russia for the nerve-agent attack on Sergei Skripal, 66, and his daughter.
British investigators have been unable to determine the source the poisoning.
Johnson responded to the claim in an article published by the Sunday Times, where he accused Corbyn of refusing to "unequivocally" blame Moscow and called him "the Kremlin's useful idiot."
"There is only one thing that gives the Kremlin succor and lends false credibility to its propaganda onslaught. That is when politicians from the targeted countries join in," said Johnson.
"Sadly, I am driven to the conclusion that Jeremy Corbyn has joined this effort ...Truly he is the Kremlin's useful idiot," he added.
Corbyn said Wednesday that Johnson had “eggs on his face” for saying that the government experts at the Porton Down laboratory were “categorical” that the nerve agent used in the attack was Novichok and had Russian origin.
This is while government experts have never specifically named the Russian government agents as the perpetrators.
Corbyn’s party, meanwhile, said Sunday that Johnson was the idiot having "undermined his own government's position" by providing evidence that was not decisive.
Dismissing Johnson’s “ridiculous insults,” Labour said they didn’t change the fact that he “has clearly misled the public over vital issues of national security.”
“Boris Johnson has made a fool of himself and undermined the government by seriously misrepresenting what he was told,” the party’s statement read.
The UK says there is "no other plausible explanation" for the Skripal attack than to blame it on Russia, while Moscow accuses London of using the case as an excuse to fuel its "propaganda war" against Russia.
The incident has seen ties between the two sides further collapse, with the UK and 23 of its allies expelling dozens of Russian politicians.
Firmly denying any fault for the attack, Russia hit back by expelling diplomats from the UK and some other countries.