Angela Rayner criticised Boris Johnson for refusing to introduce new cost-of-living measures until a new prime minister has been chosen.The deputy Labour leader believes Mr Johnson should be doing more after clinging on to the job "with white knuckles" until September."I think it's disgraceful that Boris Johnson, as the prime minister, has said 'it's not my responsibility anymore'. He's the prime minister of this country," Ms Rayner said. "Where are you? How dare you let people down when they need you so much."