Sir Keir Starmer was forced to abandon a key plank of his welfare reform agenda to get the legislation through its first Commons test.
In a late climbdown as MPs prepared to vote, the Government shelved plans to restrict eligibility for the personal independence payment (Pip), with any changes now only coming after a review of the benefit.
The move will cause a headache for Chancellor Rachel Reeves, who has seen a forecast £4.8 billion saving from the welfare budget whittled away through a series of concessions, leaving her to seek extra money through spending cuts, tax hikes or borrowing to balance the books.
The decision to remove the Pip changes from the Universal Credit and Personal Independence Payment Bill was announced just 90 minutes before MPs voted on Tuesday night.
The legislation cleared its first hurdle by 335 votes to 260, majority 75.
