Long-serving Labour MP Nick Brown has been temporarily suspended from the party - triggering the removal of the whip, pending an investigation.
The Guardian reported that a complaint has been made against the member for Newcastle-upon-Tyne East, who has previously served as Labour chief whip, the nature of which is unknown.
It is understood Mr Brown has been administratively suspended from membership of the Labour Party while an investigation is carried out.
This leads to the automatic precautionary suspension of the whip.
A statement attributed to the MP, reported by The Guardian, said: "There has been a complaint made about me to the Labour Party, which is under investigation.
"I am therefore under an administrative suspension from the Labour Party until the investigation is concluded.
"I'm not aware of what the complaint is. I am cooperating fully with the investigation."
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