The shadow work and pensions secretary has been forced to stand down while an investigation into allegations of bullying is carried out, Labour has announced.
Debbie Abrahams, who has held the role since June 2016, was replaced by her deputy Margaret Greenwood on 11 March while a "no-prejudice investigation" is held.
The investigation, being held by the party rather than parliamentary whips, is understood to relate to a number of complaints made by her staff, including allegations of bullying.
In a statement, the party said: "Debbie Abrahams has stood aside from her frontbench role while the Labour party investigates an employment issue. Margaret Greenwood will act as shadow secretary of state for work and pensions during this period."
Abrahams rejected the "spurious" claims and turned on the party leadership's office, accusing Jeremy Corbyn's staff of "aggressive, intimidating and wholly unprofessional" behaviour. She has referred her complaints to both Labour and parliamentary authorities.
"I refute the allegations that have been made against me in the strongest possible terms," she said in a statement. "I will fight this spurious claim and do not rule out taking legal action. I have had no details about the complaint, who it is from, the process or timescales. I have not agreed to stand aside.
"My treatment by certain individuals in the leader's office over the last 10 months has been aggressive, intimidating and wholly unprofessional. My treatment in the last week has shown a bullying culture of the worst kind. As such I am making a formal complaint to both the Labour party and parliamentary authorities."
Greenwood, who is MP for Wirral West, has been shadow employment minister since October 2016, and previously sat on the Environmental Audit Committee from July 2015 to December 2016.
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