Boris Johnson on Wednesday suffered a large backbench rebellion as Conservative MPs voiced their opposition to the government’s decision to delay the final lifting of lockdown restrictions scheduled for June 21.

The UK prime minister announced earlier this week that step four of the government’s ‘road map’, which would have removed all restrictions on social contact and reopened businesses including nightclubs, would be postponed for four weeks until July 19.

While the measures passed in parliament by 461 votes to 60, 49 Conservative MPs voted against the amendment, including Sir Graham Brady, chair of the 1922 committee, and Mark Harper, chair of the Covid Recovery Group and former chief whip.

The vote marks one of the largest coronavirus rebellions since the pandemic began. In December last year, 53 Tories voted against the implementation of the tiering system within England, while in October 2020, 42 MPs opposed the 10pm curfew imposed on pubs and restaurants across the country.

Speaking in the House of Commons ahead of the vote on the measures, Matt Hancock, health secretary, warned that the Delta variant, first identified in India, now accounted for 96 per cent of all new infections, while the number of hospitalisations had risen by 48 per cent in the past week.

On Wednesday, 9,055 new infections were recorded across the UK, the highest daily figure since February.

Hancock said that the government intended to use the four-week delay to offer the second vaccine dose to all over-50s and offer a first dose to every adult of 18 and over.

“The estimate is that by taking that pause in this step, we can save thousands of lives,” he said. “We have a very high degree of confidence that we can deliver the vaccines that we think are needed in order to be able to take step four on July 19.”

However, Conservative MPs voiced concern over the impact of restrictions on businesses, and questioned whether restrictions would ever be fully lifted within the country.

Former minister Steve Baker argued that the government had failed to produce a “cost-benefit analysis” of delaying the lifting of restrictions and warned against “perpetual” lockdowns.

“Thousands of pubs, restaurants and theatres have struggled by — if open at all, then hardly breaking even,” he added. “We are in danger of hollowing out and destroying the entertainment industry — much of what makes life worth living.”

Fellow rebel Desmond Swayne, Conservative MP for New Forest West, questioned the proportionality of the restrictions.

“I always thought that it was wrong for them to take our freedoms, even though they believed that they were acting in our best interests in an emergency, but by any measure that emergency has now passed and yet freedoms are still withheld,” he said.

Earlier on Wednesday, public health experts warned that variants of coronavirus would become a fact of life.

Dr Susan Hopkins, the strategic response director for Covid-19 at Public Health England, told the science and technology select committee, that PHE was currently monitoring 25 new variants, eight of which were under investigation.

“We’re living in a world of variants now, so everything we see is a variation of the original,” she said. “And so the challenge always is trying to understand which one of these is going to do something as it emerges.”