The leader of the UK's biggest trade union has accused Labour deputy Tom Watson of existing in a world of "skulduggery, smears and secret plots", as an increasingly damaging dispute over Labour's future threatens to split the party.
Unite general secretary Len McCluskey said that when the party has needed loyalty, Watson "has been sharpening his knife looking for a back to stab".
"When unity is required, he manufactures division," he wrote in a blog on the Huffington Post. "It is small surprise that he has then worked to split the party again this week. He has form as long as his arm. And now his sights are set on abusing the internal democracy of Unite."
The two former friends used to share a flat in London but have grown apart in recent years, with Watson increasingly representing the old right wing of the labour and union movement while McCluskey is closer to party leader Jeremy Corbyn.
The most recent dispute arose after The Observer was leaked a secret recording of the co-founder of the pro-Corbyn campaign group Momentum apparently suggesting it could formally link up with McCluskey's union.
In response, Watson told Sky News that this "looks like a secret plan to take over the Labour party" and "needs to be called out".
Individuals close to Watson's team say he was not attempting to start a coup against Corbyn but wanted instead to lay down a marker against any other insurgencies.
Nevertheless, his intervention infuriated McCluskey, who is currently involved in his own competition for re-election as leader of Unite, which he is expected to win. He strongly denied that there are currently any plans to affiliate with Momentum.
Attempts to patch up relations between Corbyn and Watson through a joint statement from them demanding unity were also swiftly undermined when some journalists were briefed against the deputy leader, apparently by individuals close to Corbyn.
Multiple anti-Corbyn Labour MPs present at Monday night's meeting of the parliamentary Labour party (PLP) told BuzzFeed News they are exasperated, exhausted, and despairing. But they still insist there is no desire to mount another coup attempt.
“It’s not anger, it’s just grief,” one anti-Corbyn Labour MP told BuzzFeed News, explaining that members of the PLP felt unable to maintain their “disciplined silence” after the tape was leaked.
But they have learnt the lesson of last year's leadership contest, in which a poorly organised coup resulted in Corbyn receiving another substantial mandate from party members.
Instead MPs are hoping Corbyn will go following a war of attrition, rather than after an uprising.
Even this was not enough for one despairing anti-Corbyn Labour MP: "We are actively harming our county by being so shit."
Late last night Corbyn once again called for unity in a video posted to Twitter, saying that "sometimes spirits in the Labour party can run high" and "today has been one of those days".
In a potentially unhelpful intervention, the former mayor of London Ken Livingstone waded into the row to defend Corbyn against the rest of the parliamentary party, saying: "He’s stabbed in the back by Labour MPs, he’s not going to change what he believes or the direction he’s taking."
Jim Waterson is a politics editor for BuzzFeed News and is based in London.
Contact Jim Waterson at firstname.lastname@example.org.
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