Keir Starmer has reiterated his calls for a full inquiry into government “sleaze” and the prime minister’s integrity after explosive revelations by the PM’s former chief adviser Dominic Cummings accusing Boris Johnson of cronyism. In a blogpost, Cummings alleged that the prime minister had been mulling “possibly illegal” ways to get Tory party donors to fund a refurbishment of his Downing Street flat, and denied having leaked text conversations between Johnson and James Dyson in which the PM agreed to “fix” Dyson’s tax concerns if his company made ventilators in the UK. Johnson’s former key ally further accused his old boss of seeking to shut down the Whitehall investigation into the identity of the “chatty rat” who leaked plans for England’s second coronavirus lockdown, which is still “live”, sources said on Saturday. Johnson has denied the allegations, and No 10 has suggested in briefings to newspapers that Cummings was responsible for the leak. Starmer described Johnson’s attempts to respond to these allegations as “contemptuous”. The Labour leader told BBC News: “It matters. It is about integrity, it is about taxpayers’ money. Every day, there is more evidence of this sleaze. Frankly, it stinks. “If there is nothing to see here, whether it is the refurb of No 10, whether it is the dodgy contracts, whether it is the privileged access … if there is nothing to see, publish everything, have a full inquiry. Sunlight is the best disinfectant.” On Wednesday, Starmer and Johnson clashed during prime minister’s questions over Johnson’s text exchange with Dyson. Starmer asked: “What is the right thing to do if the PM receives a text message from a billionaire supporter asking him to fix tax rules?” In response, Johnson said he would make no apology for “shifting heaven and earth” to secure ventilators and save lives.