Former North West Durham MP Laura Pidcock has quit Labour's governing body, blasting the party's "lack of vision" under Sir Keir Starmer.
Ms Pidcock, who lost her seat in 2019, accused Sir Keir of making the party a "hostile territory" for thousands of members who joined under Jeremy Corbyn's tenure.
Her decision to quit the National Executive Committee (NEC) comes 24 hours after a motion to have the parliamentary whip reinstated to Mr Corbyn was defeated.
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In a 800 word resignation letter, published this evening, Ms Pidcock said: "What I have witnessed on the NEC has been immensely frustrating.
"This leadership is devoid of ideas, lacking vision. I can’t and won’t negotiate with these people anymore.
"The summit of their ideas are just small tweaks to the status quo. They challenge virtually nothing, but are noticeably determined when it comes to rule changes that alienate the left.
"They have demoralised thousands of people who were awakened to politics for the first in their life. I am sure, this is part of their larger strategy."
Ms Pidcock also condemned the admission of former Tory MP Christian Wakeford into the Labour fold.
She said: "To be really honest, the cheering of a Tory MP crossing the floor in the House of Commons, an MP who has voted against everything we believe in, crystallised the deep unease.
"What I immediately felt was pain for all of those who are forced to use food banks, all of those who are going through the punitive ‘social security’ system, for all of the amazing activists protesting against the Police, Crime, Sentencing and Courts Bill, including Gypsy and Traveller people, who are also at the heart of resisting the racism in this legislation — some of the many reasons why this whooping by elected representatives of my own party, on that day, was so inappropriate and jarring for so many."
A Labour spokesman said: "We thank Laura for her service and respect her decision."
