In all email to all the paper's journalists, Guardian cartoonist Steve Bell has attacked his editors' refusal to run his latest cartoon, suggesting it is due to "some mysterious editorial line" about antisemitism.
In the latest submission by Mr Bell, whose cartoons have appeared in the paper since 1981, Labour deputy leader Tom Watson is depicted as an "antisemite finder general" for being critical of Jew-hate in the party.
The instalment depicts Mr Watson encountering Israeli Prime Minister Benjamin Netanyahu and calling him an "antisemitic trope".
Mr Netanyahu is playing with Donald Trump and Boris Johnson puppets and Mr Watson apologises, saying "I thought you were members of the Labour Party."
"After our bizarre telephone conversation yesterday, I feared you might not publish today's strip," Mr Bell wrote to an editor, copying in every journalist on the paper.
"You said the 'lawyers are concerned' but about what? It's not antisemitic nor is it libellous...
"I suspect the real cause is it contravenes some mysterious editorial line that has been drawn around the subject of antisemitism and the infernal subject of antisemitic tropes.
"In some ways this is even more worrying than the specious charges of antisemitism. Does the Guardian no longer tolerate content that runs counter to its editorial line?"
He went on to attack the advert taken out by Labour peers attacking Mr Corbyn over antisemitism, as "personally insulting" to the Labour leader.
He also questioned why the paper had printed and then removed an open letter defending MP Chris Williamson that the Guardian had said was from "prominent members of the Jewish community".
The Board of Deputies complained the paper had been "'misleading and inaccurate' about the signatories and noted one had "called for Zionists to be exterminated".
In his angry email, Mr Bell wrote: "Were they the wrong kind of Jews? The paper's contortions on the subjects do not do it any credit."
After this article went live, Mr Bell sent the full cartoon to the JC, saying: "Please feel free to publish them as the Guardian don’t wish to, for reasons which still remain unclear to me and, I think, to them."
Labour's Shadow Chancellor John McDonnell later entered the row, asking "Has it really come to this, the the Guardian is banning the brilliant cartoonist".
His tweet shared a famous quote about free speech that is wrongly attributed to Voltaire.
It not the first time Mr Bell has emailed all Guardian journalists to complain about allegations of antisemitism.
Last June, he emailed all journalists to say he felt "unfairly traduced and censored" after the paper would not run his cartoon of Theresa May meeting Mr Netanyahu while Palestinian Razan al-Najjar, who had been shot and killed by an Israeli soldier, burned in the fireplace behind.
He accused Guardian editor Kath Viner of not speaking to him because she "did not really have an argument" for spiking the cartoon.
In November 2012, his cartoon that depicted Mr Netanyahu as a puppeteer prompted many complaints to the press regulator.
