Boris Johnson claimed the “ructions” of the Covid pandemic can pave the way for a transformation akin to the “new Jerusalem” pledged by the postwar cabinet as he sought to restore Tory morale with an upbeat party conference speech. With Keir Starmer’s Labour party gaining in the polls, and mounting disquiet among colleagues over Johnson’s handling of the pandemic, the prime minister used his set-piece speech to set out an optimistic vision of change. Delivering his address to the virtual conference, the prime minister said the UK was and would be “the greatest place on Earth”, and that it was “the measure of the greatness of this country that we are simply not going to let [the pandemic] hold us back or slow us down”. But Labour accused him of failing to acknowledge the scale of the challenge. The party’s deputy leader, Angela Rayner, said: “The British people needed to hear the prime minister set out how he and his government will get a grip of the crisis. Instead we got the usual bluster and no plan for the months ahead.” Johnson said he was confident Britain would “repel” the virus, “just as this country has seen off every alien invader for the last thousand years” but he insisted there must be no return to “normal”. “After all we have been through, it is not enough just to go back to before. We have lost too much, we have mourned too many,” he said. “We have been through too much frustration and hardship just to settle for the status quo and to think that life can go on as before the plague, and we will not.” In a speech that pledged investment in wind power and electric vehicles, a focus on homebuilding and home ownership, and made a staunch defence of the private sector, he said the government would: Fix care home funding, hinting at the prospect of an insurance-style model. Explore the value of one-to-one teaching, both for pupils falling behind and those with exceptional abilities. Encourage 95% mortgages to help young people on to the housing ladder. Invest in high-skilled, green-collar jobs in wind, solar, hydrogen and nuclear energy, and in carbon capture and storage. Comparing the crisis to devastating wars and famines, he said: “History teaches us that events of this magnitude … they don’t just come and go. They are more often than not the trigger for social and economic change.” “In the depths of the second world war, in 1942, when just about everything had gone wrong, the government sketched out a vision of the postwar new Jerusalem that they wanted to build. And that is what we are doing now – in the teeth of this pandemic,” he went on to say. Downing Street was unable to offer any details about the policies announced, including the plan for funding social care which Johnson first claimed to have “prepared” when he arrived at No 10 last July. The Lib Dem leader, Ed Davey, who was energy secretary in the coalition government, said: “Johnson’s plans were unambitious at best – the money being spent on wind power is just a fraction of what is needed to ensure we achieve a green recovery. Equally, it is more than ironic for the prime minister to cast himself as the saviour of the care sector, given the treatment of carers by his government during this crisis.” The prime minister also faced down his critics over questions about his own health. “I’ve read a lot of nonsense recently about how my own bout of Covid has somehow robbed me of my mojo,” he said, calling the claims “self-evident drivel” and “propaganda you’d expect from people who don’t want the government to succeed”. However, he said he was “too fat”, which had exacerbated the disease – he has since lost 26lbs (11.8kg) – and he compared his condition to the UK economy. “The UK economy had some chronic underlying problems: long-term failure to tackle the deficit in skills, inadequate transport infrastructure, not enough homes people could afford to buy – especially young people – and far too many people, across the whole country, who felt ignored and left out, that the government was not on their side. And so we cannot now define the mission of this country as merely to restore normality.” Johnson said he would stop the criminal justice system from being “hamstrung by what the home secretary would doubtless, and rightly, call the lefty human rights lawyers and other do-gooders”, triggering fury in the legal profession. While he said the private sector will be at the forefront of the economic recovery, his speech outlined many new public spending commitments including the introduction of one-to-one teaching for both gifted and struggling students, and the overhaul of social care. “We will fix the injustice of care home funding, bringing the magic of averages to the rescue of millions,” he said. “Covid has shone a spotlight on the difficulties of that sector in all parts of the UK, and to build back better we must respond; care for the carers as they care for us.” However, he said free enterprise would be at the heart of future growth, a key theme of previous Johnson speeches, and sounded an early warning about the extent of state intervention on schemes such as furlough. He said Rishi Sunak had “done things that no Conservative chancellor would have wanted to do except in times of war or disaster”. “There comes a moment when the state must stand back and let the private sector get on with it,” he said. “We must not draw the wrong economic conclusion from this crisis.” He said the state would help the private sector by “becoming more competitive, both in tax and regulation”. The prime minister also set out plans briefed by Downing Street overnight to power every home in the UK with offshore wind energy within a decade, a move he said would create “hundreds of thousands, if not millions of jobs” in the next decade. He added that the UK would “become the world leader in low-cost, clean power generation – cheaper than coal and gas”, comparing its offshore wind resources to Saudi Arabia’s oil wealth. Downing Street said the initial investment would rapidly create about 2,000 construction jobs and enable the sector to support up to 60,000 jobs directly and indirectly by 2030 in ports, factories and the supply chains. In a nod to Tory backbenchers who have threatened to vote down any future curbs on freedoms because of the pandemic, Johnson said he hoped there would be no more restrictions on daily life by the time of the next Conservative conference in 2021. Hours after his speech, 12 Conservative MPs voted against approving the “rule of six” regulation which limits social gatherings. Rebels included the chair and a vice-chair of the backbench 1922 Committee, Graham Brady and Charles Walker, a select committee chair Huw Merriman and the former cabinet minister Esther McVey. Johnson is likely to face more opposition when MPs are due to approve the 10pm curfew. Tory MPs and the Labour frontbench have called on the government to publish further evidence of its effectiveness. The Tory former minister Steve Baker said people were being “destroyed by this lockdown, strong, confident people, outgoing people, gregarious people … reduced to repeated episodes of tears on the phone”.