The UK Foreign Office and the White House have both said evidence heavily suggests Tehran planned the attacks and on Friday produced a video said to show an unexploded mine being removed from one of the vessels by Iranian special forces.
In a tweet on Friday evening, Corbyn suggested the evidence presented was not “credible” and called for restraint, a comment seized upon by senior Tories.
Jeremy Hunt branded the Labour leader “pathetic and predictable” and highlighted previous times Corbyn has doubted intelligence assessments.
Corbyn’s made similar comments in response to the poisoning of Sergei Skripal last year when he suggested “Russian mafia-like groups” could have been behind the attempted murder, not the Kremlin.
Skripal and his daughter Yulia were poisoned by a deadly military-grade nerve agent and extensive evidence has since been presented of the identities, military records and links to the Russian government of the two suspects in the affair, and European arrest warrants have been issued.
Sajid Javid said Corbyn was “never on the side of the country he seeks to lead”, adding: “Never mind whether he’s qualified to be PM of our great country - based on his past associations alone, Corbyn wouldn’t even qualify for a Home Office building pass.”
Other commentators highlighted how Corbyn has in the past earned money from appearances on Iranian state TV.
In 2016 Corbyn was branded a “hypocrite” for criticising other countries’ dire human rights record while taking money from the Iranian government for appearances on the country’s state TV channel, Press TV.
Corbyn’s comments were echoed by shadow foreign secretary Emily Thornberry, who said US hardliners like national security adviser John Bolton were trying to engineer regime change in Iran.
“These are extremely dangerous developments and we really have to pause and think about where we are going next,” she told the BBC Radio 4 Today programme.
Corbyn did have one prominent supporter however, actor Rob Delaney said: “I speak for America... when I say Thank You.”
The price of oil rocketed on Thursday amid fears of disruption to one of the world’s most important tanker routes as a result of instability in the region.
The suspected attacks came after four commercial ships were “subjected to sabotage operations” in the Arabian Gulf in May.
The FCO said a UAE-led investigation concluded that they were conducted by “a sophisticated state actor”.
“We are confident that Iran bears responsibility for that attack,” the FCO said.