Labour’s deputy leader Angela Rayner has been warned not to mistake as “friends” factions of her party who want to damage Keir Starmer.

       Labour grandee Peter Mandelson hit out after reports allies of Ms Rayner were sounding out MPs over a possible leadership challenge if the party lost the Batley and Spen by-election.

       In the end Labour held on, albeit with a slim majority of just over 300 votes.

       Within hours of the result of a leading union also publicly distanced itself from any leadership campaign.

       The Communication Workers Union said it was “definitely not true” that Ms Rayner had its support.

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       Earlier Lord Mandelson, a former architect of New Labour, accused some within his party of conspiring against the leader.

       He told Radio 4’s Today programme: “Let’s been honest here – there were elements of the Corbynite left who seemed far too eager during this campaign for (George) Galloway’s presence to result in a blow to Keir Starmer and his leadership ... while others were campaigning in Batley, they were conspiring. They should now stop their whispering.”

       In a challenge to the party’s deputy leader, he added: “Angela Rayner, she should realise these people are not her friends… (they are) serving their own factional interests.”

       But he also warned that not enough voters see Labour as a potential party of government and urged Sir Keir to use his party conference speech in September to set out his stall to a wider audience.

       Sir Keir, who hailed the result as a “very important moment” which showed that “Labour is back”, vowed voters would see more of him this summer, following accusations too few know what he stands for .

       He told journalists that the pandemic had made it difficult for him to set out Labour’s stance on the future of the UK. “As we come out of the pandemic .. .the space finally opens up for me to make the argument,” he said, “…that’s what I will be doing in the summer and into conference… (talking) about health and social care and education and work,” he said.