The deputy Tory leader suggested it was “very likely” that Ms Haigh herself had been among those MPs.
Last summer, as a backbencher, Ms Haigh was instrumental in organising a Labour revolt against Sir Keir’s proposals to trim £5billion annually from disability benefits.
That rebellion ultimately forced a humiliating U-turn. Mr Burnham, then serving as Greater Manchester’s mayor, had also opposed the cuts.
Mr Burnham’s 10-year plan, expected before the year is out, has been billed as the moment his premiership truly begins. In an ITV interview this week, he insisted it would represent “the radical moment” when the public would finally see his ambitions realised.
On the plan’s substance, Mr Burnham offered a broad outline focused on “public control” over essential services, with energy policy at its core. He spoke of making power more affordable and accelerating grid connections for businesses.