02/08/2016 16:00 BST | Updated 02/08/2016 16:46 BST

Owen Jones Accused Of 'Back-Stabbing' Jeremy Corbyn By Union Leader Manuel Cortes

'I would not like to be in a trench alongside Owen under heavy shelling'

Rick Findler/PA Archive

Owen Jones has been accused by a union leader of “back-stabbing” and waging a year long campaign behind closed doors against Jeremy Corbyn.

Writing for The Huffington Post UK on Tuesday, Manuel Cortes, the general secretary of the Transport Salaried Staffs’ Association (TSSA), suggested the prominent Guardian columnist and campaigner was motivated by the “petulant resentment” of “a celeb no longer quite as centre-stage as he was accustomed to being”.

On Sunday, Jones, who campaigned for Corbyn during the 2015 Labour leadership election, wrote a lengthy blog warning that the party was on the “brink of disaster”.

He has also written a follow up post in an attempt to win over fans of Corbyn who criticised his initial piece.

But in a fierce attack, Cortes, who is backing Corbyn’s continued leadership of Labour, said Jones makes “Simon Cowell look like a paragon of understated modesty”.

The union leader also claims Jones turned down the offer to work for Corbyn when it was offered in August last year.

Jonathan Brady/PA Wire
Owen Jones give a speech during the March for Europe rally in Parliament Square, London to show support for the European Union in the wake of Brexit.

Cortes wrote: “Owen Jones’s ‘Questions all Jeremy Corbyn supporters need to answer’ is the public climax to a private campaign of criticism of the Labour leader which Owen initiated within 24 hours of Corbyn’s election last September.

“Barely had the votes been counted to give Jeremy his unprecedented mandate than Owen was embarking on his ‘it’s all going wrong’ shtick to anyone who would listen.

“Some may now see this as the act of one whose prescience borders on genius, others as a campaign of petulant resentment by a celeb no longer quite as centre-stage as he was accustomed to being.

“Whatever, his assertion that ‘I cannot even begin to put into words how much I’ve agonised over Labour’s terrible plight’ is the one flat untruth in his blog, as can be attested to by anyone who has suffered his foaming hour-long reviews of the disasters that have attended Team Corbyn’s failure to follow his advice to the letter.”

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In his blog for The Huffington Post UK, Cortes said the current Labour leadership contest, which sees Owen Smith fighting to take over from Corbyn, is a “moment for solidarity, not back-stabbing”.

He added: “I would not like to be in a trench alongside Owen under heavy shelling.  The events of the last month, which he mainly ignores, have represented an unprecedented attack on an elected Leader of the Party.  They are part of a move to break the power and influence of the Left that Owen claims to represent.”

In Jones’ original blog, which Cortes responded to, the Guardian columnist revealed how he has “agonised over Labour’s terrible plight”, and spelled out in brutal detail how the party under Corbyn’s leadership faces “calamitous” polling, is short of a “clear vision”, and does not have “any clear” media strategy.

He feared Labour being “wiped out as a political force”, and “anything vaguely left-wing” being “mocked for the rest of your life” and a “throwback to the discredited Labour era of the 2010s”.

Jones, a long-standing supporter of Corbyn, writes he is “beyond caring” if his criticism causes discomfort and recognises he risks being labelled a “Blairite, Tory, Establishment stooge”.