Labour welfare rebels have threatened to set up a rival party if Keir Starmer kicks them out for voting against his plan to cut benefits.
Senior ministers including Deputy PM Angela Rayner have refused to rule out stripping party MPs of the whip if they oppose changes to payments for disabled people.
The package of reforms is aimed at encouraging more people off sickness benefits and into work, but dozens of Labour rebels said last month that the proposals were 'impossible to support'.
Some 170 are said to have raised concerns, meaning it is possible it will be the largest rebellion of Sir Keir's time in power so far.
They are unhappy at the hard line emanating from No10 with threats of being suspended, with one telling Politico: 'You can't do that to 170 MPs, we'll just go off and form Labour 2.
