The prime minister was speaking as he welcomed leaders including Joe Biden, Angela Merkel and Emmanuel Macron to the first round-table session of the summit of leading democracies in Cornwall.
Mr Johnson said that world powers must ensure that the coronavirus pandemic does not leave a “lasting scar” of deeper and more entrenched inequality.
And he told his fellow leaders they should be aiming at “building back greener, building back fairer and building equally and – how should I put it? – in a more gender-neutral and perhaps a more feminine way.”
Mr Johnson appeared to acknowledge the damage done by the austerity policies of Conservative-led governments in the wake of the 2008 financial crash, urging today’s leaders not to fall into the same trap while plotting the recovery from Covid.
“It is vital that we don’t repeat the mistake of the last great crisis, the last great economic recession in 2008, when the recovery was not uniform across all parts of society,” he said.
“I think what’s gone wrong with this pandemic – or what risks being a lasting scar – is that I think that inequalities may be entrenched.
“We need to make sure that as we recover, we level up across our societies and we we build back better.”
Describing the better world which he hopes will result from the recovery, Mr Johnson said: “As a G7, we are united in our vision of a cleaner, greener world, a solution to the problems of climate change.
“And in those ideas, in those technologies – which we’re all addressing together – I think there is the potential to generate many, many millions of high-wage, high-skill jobs.
“And I think that is what the people of our countries now want us to focus on.
“They want to be sure that we’re beating the pandemic together discussing how we will never have a repeat of what we’ve seen, but also that we’re building back better together. Building back greener, building back fairer and building equally and – how should I put it? – in a more gender-neutral and perhaps a more feminine way.”
Asked later what the PM meant by rebuilding in a “feminine” way, foreign secretary Dominic Raab told ITV News: “For example, one of the things we found with Covid is that a lot of children in the poorest countries around the world, out of education, the girls are the last – the laggards if you like – in getting back into education.
“That is why we’ve just announced £430m – a five-year pledge – into the global partnership for education, which is contributing towards our global target of getting 40 million girls back into education.”
Recovery from the pandemic is top of the agenda for leaders of the G7 nations – the US, UK, France, Germany, Italy, Canada and Japan – at Carbis Bay in Cornwall.
They agreed on Friday to donate 1 billion doses of vaccine to help poorer countries protect their populations against the virus – thought campaigners argue that this is not enough without the finance to drive the rapid inoculation of all the world’s people.