George Galloway has been suspended from the Labour Party pending "internal party investigations".
The MP is at the centre of claims he was in pay of Saddam Hussein.
Mr Galloway immediately hit back at the suspension, describing it as "completely unjust" and "prejudicial" to his libel action against the Daily Telegraph.
Party General secretary David Triesman said the suspension, effective immediately, would remain in place "pending internal party investigations".
PA
