By Guy Faulconbridge and Kate Holton

LONDON (Reuters) – British Prime Minister Boris Johnson said on Monday he would plot a cautious but irreversible path out of the COVID-19 lockdown this week after the vaccination of 15 million vulnerable people.

With nearly a quarter of the United Kingdom’s population now inoculated with a first dose of a COVID vaccine in a little over two months, Johnson is under pressure from some lawmakers and businesses to reopen the shuttered economy.

“We’ve got to be very prudent and what we want to see is progress that is cautious, but irreversible,” Johnson told reporters. “If we possibly can, we’ll be setting out dates.”

“If because of the rate of infection, we have to push off something a little bit to the right – delay it for a little bit – we won’t hesitate to do that.”

Johnson, due to set the path out of lockdown on Feb. 22, said the rates of infection were still high and too many people were still dying.

Asked if he would ensure schools reopened on March 8, Johnson said he would do everything he could to ensure that.

If many people get infected, there would be a high risk of mutation in the virus and higher risk of it spreading to older and more vulnerable groups, he said.

The biggest and swiftest global vaccine rollout in history is seen as the best chance of exiting the COVID-19 pandemic which has killed 2.4 million people, tipped the global economy into its worst peacetime slump since the Great Depression, and upended normal life for billions.

The United Kingdom has the world’s fifth-worst official death toll – currently 117,166 – after the United States, Brazil, Mexico and India.

VACCINE PASSPORTS?

Britain has vaccinated 15.062 million people with a first dose and 537,715 with a second dose, the fastest rollout per capita of any large country. Hancock said he expected vaccine supplies to increase as manufacturing accelerated.

An influential group of lawmakers in Johnson’s Conservative Party is urging an end to the lockdown as soon as the most vulnerable nine groups are vaccinated. They want no more rules beyond May 1.

“We’re all filled with sorrow for the people we’ve lost, the harms that we’ve suffered but we don’t honor those we’ve loved and lost by wrecking the rest of our lives,” lawmaker Steve Baker said. “We’ve got to find a way to rebuild our society and our economy and our prospects, our livelihoods.”

Britain is speaking to other countries about giving its citizens certificates showing they have been vaccinated so that they can travel abroad in the future to countries that require them, Johnson said.

“That’s going to be very much in the mix, down the road I think that is going to happen,” Johnson said, referring to such certificates. “What I don’t think we will have in this country is, as it were, vaccination passports to allow you to go to the pub, or something like that.”

(Reporting by Guy Faulconbridge and Kate Holton; Editing by Peter Graff, Nick Macfie and Bernadette Baum)