Moves to oust Tom Watson as Labour’s deputy leader have provoked controversy.
Labour’s National Executive Committee (NEC) is to vote on whether to abolish the position of deputy leader on Saturday.
Mr Watson has publicly clashed with Jeremy Corbyn on a number of occasions.
He recently called for a new Brexit referendum to be held before a general election.
Labour’s NEC is to consider abolishing the post of deputy party leader on Saturday after a bid to get rid of the post failed at a meeting on Friday.
Former Labour leader Ed Miliband tweeted: “The move to abolish the deputy leader post without warning or debate is undemocratic, wrong and should not happen.
“Those who came up with the idea for the eve of Labour conference have taken leave of their senses.”
Ex-minister Yvette Cooper tweeted: “This is completely mad and incredibly destructive. Country faces serious challenges & General Election could be imminent. @UKLabour conference shd be about country & about pulling together. Instead we get this.”
Founder of the pro-Jeremy Corbyn group Momentum Jon Lansman proposed a motion to scrap the post of deputy leader on Friday.
It is understood the chair of the NEC ruled the motion out of order before members voted 17 to 10 hear it.
The situation will be discussed by the NEC on Saturday ahead of Labour’s annual conference.
A source close to Mr Watson told PA news agency that the situation was “completely outrageous”.