Starmer allies issue warning to PM’s rivals as fears grow over leadership challenge

Exclusive: No 10 said to be in full bunker mode' over fears of attempt to oust him after budget or May local elections

• Thin majorities and chaotic strategy push Labour MPs toward regime change

Downing Street has launched an extraordinary operation to protect Keir Starmer amid fears among the prime minister's closest allies that he is vulnerable to a leadership challenge in the wake of the budget.

Starmer's most senior political aides warned that any attempt to oust the prime minister over tanking poll ratings would be a reckless" and dangerous" move that could destabilise the markets, international relationships and the Labour party.