Robert Jenrick has published private texts allegedly from a Tory official after the party's leader, Kemi Badenoch, accused him of lying.
It comes after the MP, who defected from the Conservatives to Reform UK last week, claimed Tory chief whip Rebecca Harris contacted him in 2024 to say there was "a special place in hell" for him.
He alleged Ms Harris "messaged me with a litany of insults" after he wrote an article for the Mail on Sunday, in which he called for the UK's foreign aid budget to be halved to fund an increase in defence spending.
When quizzed about the allegation, Mrs Badenoch said Mr Jenrick was "lying" about the exchange and said it was her party's policy to spend more money on the British military and "take it away from aid".
Mrs Badenoch told GB News earlier on Friday: "He's lying. And I think it's a real shame he's being allowed to air these views. He's left the party – it's time for him to move on."
But hours later, Mr Jenrick posted an image of messages purporting to be from Ms Harris, which he captioned with the words: "They still won't tell the truth."
According to the purported texts, the chief whip told Mr Jenrick: "This is actual feedback / Leave the party and be a commentator... Go away... You're a bloodsucker.
"You have a really special place in hell".
She allegedly continued: "Running us down in public just to feel good on heaven knows what basis / if you aren't happy with the direction of travel fine – please use your party connections to deal with it but not in public – best announce you and Suella [Braverman] are stranding [sic] down now."
"You've lost the plot," Ms Harris appears to add.
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A Conservative Party source responded to the post by accusing Mr Jenrick of "lying again and misrepresenting an exchange he had over two years ago".
They added: "Those messages have absolutely nothing to do with cutting foreign aid. Instead, they show a government whip trying to reason with someone who was working with the 'Grid of Shit' plotters, and whose scheming helped contribute to a Labour landslide and the worst result for the Conservative Party in its history.
"With his love of backstabbing and psychodrama, Jenrick will fit right in with Reform."
The row is the latest twist in a heated war of words between Mr Jenrick and his former party following his defection.
Despite the apparent reference to Ms Braverman in the text by Ms Harris, she remains a member of the Conservatives and has not left the party.
(c) Sky News 2026: Robert Jenrick and Kemi Badenoch accuse each other of lying over 'special place in hell' messag
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