In her resignation letter, Duffield denounced Starmer for pursuing “cruel and unnecessary” policies.

“The sleaze, nepotism and apparent avarice are off the scale,” she wrote after it emerged earlier this month that Starmer had accepted more than £100,000 in gifts and hospitality while cutting an annual £300 winter heating payment to pensioners.

Duffield also attacked the prime minister’s decision to maintain a cap on a benefit aimed at supporting families with children.

“Someone with far-above-average wealth choosing to keep the Conservatives’ two-child limit to benefit payments which entrenches children in poverty, while inexplicably accepting expensive personal gifts of designer suits and glasses costing more than most of those people can grasp – this is entirely undeserving of holding the title of Labour Prime Minister,” she wrote.

Duffield said that she would in future sit as an independent MP “guided by my core Labour values”.