Boris Johnson has said “absolutely nothing and no one” will stop him continuing in office, during his first prime minister’s questions since an unconvincing victory in a confidence vote among Tory MPs. In a noisy Commons, with some cheers and shouts of “more!” from loyal backbenchers, Johnson sought to present himself as fully in charge despite more than 40% of his MPs voting on Monday for him to leave No 10. Speaking for Labour, Keir Starmer questioned Johnson over waits for hospital and GP appointments, but also mocked the prime minister more generally as someone who had lost the faith of his MPs and could not be trusted to improve. But in a bullish opening, Johnson replied defiantly to a question by the Labour former minister Angela Eagle, who said he was “loathed” by his own party, adding: “Can the prime minister explain, if 148 of his own backbenchers don’t trust him why on earth should the country?” Johnson said his political career had “barely begun”, arguing he had acquired enemies due to some “very big and very remarkable” achievements. He added: “And what I want her to know is that absolutely nothing and no one, least of all her, is going to stop us with getting on delivering for the British people.” Focusing all his questions on NHS delays, during what Downing Street has billed as “health week” when it comes to government messaging, Starmer castigated Johnson for trying to pass off “paint jobs and fix-ups” to crumbling NHS infrastructure as new hospitals. “Oh dear, prime minister,” the Labour leader said. “Pretending no rules were broken didn’t work. Pretending the economy is booming didn’t work. And pretending to build 40 new hospitals won’t work either. They want him to change, but he can’t. As always with this prime minister, when he’s falling short he just changes the rules and lowers the bar.” Starmer used dissent among Tory MPs to attack Johnson, citing a hugely condemnatory letter from Jesse Norman on Monday in which the former Treasury minister said the prime minister lacked “a sense of mission” and had no long-term plan. “The prime minister’s ‘big plan’ act is so tired that even once-loyal MPs don’t believe it,” Starmer said. He also raised a series of tweets by the culture secretary, Nadine Dorries, a former health minister, in which while attacking the ex-health secretary Jeremy Hunt she appeared to concede the government’s pandemic planning before Covid had been lacking. Covid was “an entirely novel virus for which the whole world was unprepared”, Johnson said in defence. Explaining future plans, Johnson said he would be “expanding home ownership for millions of people”, a reference to a speech expected on Thursday in which he will resurrect a longstanding Conservative plan to extend right-to-buy discount schemes to housing association tenants.