Labour’s deputy leader has hit out at the outgoing Prime Minister’s apparent refusal to offer financial support to struggling families.
Mr Johnson, who is expected to leave office in September, ruled out new measures until a successor had been chosen.
A spokesperson for the Prime Minister said a raft of measures were introduced at the start of the summer.
But added: “By convention it is not for this Prime Minister to make major fiscal interventions during this period. It will be for a future prime minister.”
Ms Rayner, speaking at a nursery in Edinburgh, told the PA news agency the response lets “people down” when the urgently need support.
She said: “I think it is disgraceful that Boris Johnson, as Prime Minister, has said ‘it’s not my responsibility any more’.
How dare you let people down when they need you so much?
“He’s the Prime Minister of this country. (He) wanted that job, clung onto it with white knuckles at a time when the British public had said: ‘Actually mate, you’ve lied to us, you’ve deceived us, we don’t want you any more.'”
Addressing Mr Johnson, she said: “He’s carried on and said he needed to stay on until September. Well, where are you?
“How dare you let people down when they need you so much?
“They voted and elected you and you’ve literally just laughed at them when they need your support right now.”
Her comments come as former Labour prime minister Gordon Brown called on Mr Johnson and Conservative leadership candidates Liz Truss and Rishi Sunak to agree on emergency cost-of-living measures.
And Ms Rayner said both candidates were ill-equipped to deal with the cost-of-living crisis, and were instead solely focused on appeasing Tory members.
Former chancellor Mr Sunak came under fire last week after a leaked video showed him tell Tory voters in Kent he had redistributed funds from “deprived urban areas” to wealthy towns.
Forecasts of a recession and the worst cost of living crisis in a generation.
But the Conservative government has no plan to fix their mess. pic.twitter.com/qfQixV7nYa
— The Labour Party (@UKLabour) August 9, 2022
Ms Rayner added: “Both of them have been navel-gazing at their true blue membership and negated and decided to totally ignore the rest of the population.
“They’ve had no answers to the cost-of-living crisis. Nobody’s bothered. Boris Johnson’s gone on holiday and doesn’t really care about what people are facing at the moment.”
She added: “That to me is a dereliction of responsibility and both of those two candidates are responsible for that.”