Diane Abbott has been suspended from the Labour Party pending an investigation.
A party spokesperson confirmed the decision to Sky News but did not give a reason why.
Politics Live: The Starmtroopers are coming for the Corbynites
It comes after the veteran MP defended previous comments about racism which sparked an antisemitism row and led to a year-long suspension.
She apologised at the time and was readmitted back into the party just before last year’s general election.
A Labour Party spokesperson said: “Diane Abbott has been administratively suspended from the Labour Party, pending an investigation. We cannot comment further while this investigation is ongoing.”
Sky News understands that the suspension is not related to the four rebels who lost the whip yesterday for “repeated breaches” of party discipline, including voting against the government’s welfare cuts.
Spies and special forces among more than 100 Britons whose details were included in Afghan data leak
Politics latest: Diane Abbott suspended from the Labour Party
Starmer defends suspending rebel MPs after backbench criticism
The investigation will look into comments in which she seemingly did not apologise for the controversy she sparked in April 2023.
In a letter to The Observer which drew heavy criticism at the time, Ms Abbott argued that people of colour experienced racism “all their lives” and said that was different to the “prejudice” experienced by Jewish people, Irish people and Travellers.
Shortly after it was published, she issued a statement in which she said she wished to “wholly and unreservedly withdraw my remarks and disassociate myself from them”.
However in a new interview with BBC Radio 4’s Reflections programme this week, she said she did not look back on the incident with regret.
She said: “Clearly, there must be a difference between racism which is about colour and other types of racism because you can see a Traveller or a Jewish person walking down the street, you don’t know.
“But if you see a black person walking down the street, you see straight away that they’re black. They are different types of racism.”
She added: “I just think that it’s silly to try and claim that racism which is about skin colour is the same as other types of racism.
“I don’t know why people would say that.”
Ms Abbott is the longest-serving female MP in the Commons, giving her the title “Mother of the House”.
She made history when she was elected as Britain’s first black female MP for Labour in 1987.
As an MP on the left of the party she has often clashed with the leadership throughout her career – bar her time serving in Jeremy Corbyn’s shadow cabinet.
Many MPs rallied in support of Ms Abbott last year when it was not clear if she would be reinstated in time for the general election, or allowed to stand.
She went onto retain her seat of Hackney North and Stoke Newington with a majority of over 15,000.
A source close to the matter told Sky News that she was readmitted last year after apologising and doing antisemitism training, so there is a “very slim chance” she will be allowed back in this time.
It raises questions about whether she could join the new party being formed by Mr Corbyn and former Labour MP Zarah Sultana.
