Labour is set to ban members from backing politicians who have been suspended or leave the party.
The measure, being considered by Labour’s National Executive Committee (NEC), will stop members supporting former party politicians when they stand as independents against Labour candidates.
The proposed move is expected to affect supporters of former Labour leader Jeremy Corbyn and Jamie Driscoll.
Driscoll, the North of Tyne mayor who has been dubbed the “last Corbynista in power”, was prevented from standing for election in 2024 following a recent on-stage discussion with Ken Loach.
The film director, who was expelled from Labour in 2021, has criticised the decision. Driscoll later resigned from the party and is standing as an independent in the North East mayoral election in May next year.
Meanwhile, Corbyn was elected as leader of the Labour Party in 2015 and resigned following a historic defeat at the 2019 general election.
The Islington North MP was later ousted from Labour following a row over antisemitism. Corbyn criticised Labour leader Sir Keir Starmer and claimed he had "launched an assault on the rights of his own Labour members."
Corbyn currently serves as an independent MP after having the Labour parliamentary whip taken away but has remained a member of the party. He hinted earlier this year that he may stand as a candidate for Mayor of London.
The proposed changes will make clear that party membership will be terminated if individuals provide “financial support or assistance to, or otherwise support an individual that stands in opposition to, or declares an intention to stand in opposition to, a Labour Party candidate in a public election."
Under current rules, people cannot be members of Labour if they support rival parties and organisations.
Adam Langleben, national secretary of the Jewish Labour Movement (JLM), welcomed the move. He told the JC: "Anyone who campaigns for an independent such as Jamie Driscoll and Jeremy Corbyn cannot be a member of Labour."
John McDonnell, who served as shadow chancellor during Corbyn’s time as Labour leader, recently urged Starmer to let him back into the party.
He said earlier this month: “What is Jeremy going to do if he’s re-elected as a Labour MP? What harm is he going to do?
“He is going to concentrate on what he has done for most of his political life, foreign affairs and human rights.”
A Labour source said the party were "closing a loophole." If approved by the NEC, the plans will need to be approved by delegates at the party conference next week.