JOHN McDonnell said he takes full responsibility a few days ago for Labour's disastrous election fail.
But who is John McDonnell and what is the plan for the Shadow Chancellor now? Here's all you need to know.
Who is John McDonnell and when did he become an MP?
John McDonnell is a MP for Hayes and Harlington and has been since 1997.
He has been Shadow Chancellor of the Exchequer in the Shadow Cabinet of Jeremy Corbyn since 2015.
Has John McDonnell quit as Shadow Chancellor?
McDonnell confirmed that both he and Jeremy Corbyn will leave their posts within the next eight to 10 weeks and suggested he would like to see Rebecca Long-Bailey take the role as Labour leader.
What's John McDonnell's constituency?
Hayes and Harlington, but a fight broke out after it was announced he had won his seat last Friday.
Protesters screamed "terrorist" by protesters as a fight broke out during his victory speech this morning.
The Shadow Chancellor was speaking after winning his Hayes and Harlington seat, which he has held since 1997, when at least two men began shouting from the crowd.
McDonnell, who said Labour's election defeat was not caused by its "policy programme", was called a "terrorist" by one of the men before a fist fight broke out.
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The scuffle, which was captured live on Sky News, was quickly broken up by police officers in attendance.
It is unclear if any arrests were made.
A Sky News reporter claimed one of the men was "punched in the head."
As McDonnell finished his speech he was called a "liar" by one of rowdy men.
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