Former prime minister David Cameron has backed the introduction of Covid passports to gain entry to pubs and other venues, saying they could be vital to get the economy back up and running quickly.
The former Tory leader likened the jab to childhood vaccinations for diseases like tuberculosis that are 'almost compulsory' in an interview with US network CNN.
Ministers are mulling a 'Covid clear' system for people to prove they have tested negative or had a vaccine help open up pubs and sporting events.
The idea is understood to be under consideration as part of the government's drive to get the country up and running again.
But Boris Johnson has cast some doubt on the idea, saying it could be 'discriminatory' against people who 'genuinely' refuse jabs or cannot have them for valid reasons.
In a wide-ranging interview Mr Cameron said: 'I'm not against it. Ultimately, there are certain vaccinations that we're encouraged to have when we're children that are almost compulsory.
'If we want to open up our economy as rapidly as possible, I think there will be a number of different ways and places where people will want to know have you been vaccinated before you joined this event.'
The former Tory leader likened the jab to childhood vaccinations for disease like tuberculosis that are 'almost compulsory' in an interview with US network CNN.
Boris Johnson (pictured today) has cast some doubt on the idea, saying it could be 'discriminatory' against people who 'genuinely' refuse jabs or cannot have them for valid reasons.
He added: 'I think it's coming. I'm very glad that the government is having a serious think about all the moral and ethical and legal dilemmas. (But) They should not close their mind to this.
'I haven't come up with the answer but they should definitely keep an open mind and have a good look because we've got to try and get back to normal and normal is getting as many people vaccinated as possible.'
The PM has ordered Michael Gove to carry out a review of whether a wider system of Covid certification can be used to help reopen the UK.
This is despite vaccines minister Nadhim Zahawi previously repeatedly denying that there were plans to introduce them, saying they were 'discriminatory'.
One option understood to be on the table would involve businesses able to check test results on the NHS app. Individuals would be able to show that they have either had a jab or tested negative - maintaining their choice about vaccination.
Government sources stressed that no decisions have been taken and work is at an early stage. But supporters say such a concept could help theatres, cinemas, sporting venues and workplaces get back towards normality more quickly.
Sir Jonathan Montgomery, who has led an evidence review into vaccine passports, said this week that the idea would come too late to save summer because people would need two jabs to qualify and most young people won't have both until the autumn.