The Labour leader’s spokesperson accused the new Independent Group of being an “establishment coalition” that backed “austerity, corporate tax cuts [and] privatisation”.
As three Conservative MPs also left their party to join the new centre-ground set, the Corbyn-backing Momentum activist group branded them a “Blairite-Tory coalition” that would represent the “super rich”.
Meanwhile pro-Corbyn MPs questioned their ex-colleagues’ motives, with one suggesting Jewish MP Luciana Berger had not tried to bring antisemitism to the leader’s attention, saying “it takes two to tango”.
It came as the party announced it would consult on plans to force by-elections on MPs who changed sides mid-term, though they were not cleared with the shadow cabinet and deputy leader Tom Watson later branded them “spiteful”.
In a further sign of Labour turmoil, shadow trade secretary Barry Gardiner made a formal complaint about the re-admittance of Derek Hatton, expelled from the party by Neil Kinnock in the 1980s.
The attacks on those who have left Labour from Corbyn-backers struck a markedly different tone from a previous commitment to hold a “mammoth listening exercise” in response to the eight resignations over antisemitism, Brexit and Mr Corbyn’s leadership.
Speaking after prime minister’s questions, at which neither of the two main party leaders addressed the departures, Mr Corbyn’s spokesperson said it “regretted” MPs had left Labour.
But then added: “The fact is they have formed what is effectively an establishment coalition based on the failed and rejected policies of the past – austerity, corporate tax cuts, privatisation.
“And it’s precisely because those policies were seen to have failed and been rejected that the direction of the Labour Party changed when Jeremy was elected and we demonstrated that a different approach has mass electoral appeal and we will continue to pursue those policies and that approach.”
Momentum’s national coordinator Laura Parker also piled in, accusing those who quit of acting in an “unfair, undemocratic and dishonest” way.
She said: “It’s clear that the new party is a Blairite-Tory coalition aimed at resurrecting a dead agenda of privatisation, deregulation and tax cuts for the super rich.
“This is not what their constituents voted for. Umunna, Leslie and Smith’s constituents overwhelmingly voted Labour and have ended up with an MP in coalition with the Tories.”
Corbyn-ally Chris Williamson was asked in a television interview if it was acceptable that the leader had not met Ms Berger since 2017, despite her having been on the receiving end of substantial antisemitic abuse.
He replied: “Jeremy has reached out to Luciana. I don’t know the details. But obviously it takes two to tango.
“Obviously the opportunity was there for somebody who was feeling abused in that sense to approach Jeremy.”
A senior Labour source confirmed that a consultation had been launched by shadow cabinet office minister Jon Trickett with leadership approval on a plan to allow voters to stage recall petitions when MPs switch sides.
Mr Trickett said: “Communities should not have to wait for up to five years to act if they feel their MP is not properly representing their interests, especially with the restrictions of the Fixed-term Parliament Act.
“This proposed reform has the dramatic potential to empower citizens and will be one of many measures the Labour Party is planning to consult on and announce that will change the way politics in this country is done.”
But it emerged later in the day that the measure had not been signed off by the shadow cabinet, and Mr Corbyn’s deputy Mr Watson said he did not agree with it.
He said: “I didn’t know he was going to do that but it seems to me that whatever the merits of the position that he is putting on recall elections and resigning from parties, it just looks spiteful.
“Those people that left the Labour Party did so with a heavy heart, and it looks like we are kind of reflexive and trying to be knee-jerk about it, rather than looking at the actual issue which is Brexit and the state of British politics.”
After it emerged that former Militant leader Mr Hatton had been allowed to rejoin the party, shadow cabinet member Mr Gardiner wrote to general secretary Jenny Formby to complain.
He said: “I think it was a travesty that, at least I think many of us knew for some while that he had applied to rejoin the party, but for the news of his readmission to come to public attention on the very day when some members of our party were forced out – I think it was appalling.”
Labour has since confirmed Mr Hatton has once again been suspended over a tweet posted in 2012.
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