Video report from ITV News UK Editor Paul Brand
The UK government has said it will "facilitate" vaccine passports for international travel but this latest move could see 'Covid status certificates' used within the UK.
They could identify people with vaccine immunity which would allow businesses to ensure their employees have had the jab or could be used to allow people to enter hospitality venues.
Political Correspondent Romilly Weeks explains the likelihood of vaccine passports
Mr Johnson admitted it was a "complex issue" with risks of discrimination against people who decide not to have the vaccine.
So, what could it mean for businesses, employees or even going to the pub?
What has the government said?
The government is to review the "complex" and "ethical" issues associated with allowing businesses to have a mandate to require their employees, customers and potentially service users to have a vaccine.
The study into the use of vaccine and testing certificates will be one of four reviews conducted as part of easing the current restrictions.
If the review signs off on the use of Covid status certificates, it could mean venues or businesses could deny someone access if they cannot provide evidence that they have been vaccinated against or tested negative for coronavirus.
Outlining each review in the House of Commons on Monday, Mr Johnson said: “The third review will consider potential role of Covid status certification in helping venues to open safely.
“We are mindful of the many concerns surrounding the exclusion, discrimination and privacy.”
He added: “There may well be a role for certification but we just need to get it right.”
The four reviews, which will include looking at the current social distancing measures and how to increase international travel, are investigating matters upon which ministers do not currently feel they have enough data or information.
The findings of the vaccine passport probe are hoped to be available before stage four of the lockdown easing on June 21 is reached – the earliest date by which ministers hope all restrictions can be lifted.
Speaking on Tuesday, Mr Johnson said: “This is an area where we’re looking at a novelty for our country, we haven’t had stuff like this before, we’ve never thought in terms of having something that you have to show to go to a pub or a theatre.
Pimlico Plumbers owner Charlie Mullins says all employees must have Covid jab - and he wouldn't employ a pregnant woman who hadn't had a vaccine
“There are deep and complex issues that we need to explore, and ethical issues about what the role is for Government in mandating or for people to have such a thing or indeed in banning from people doing such a thing.
“We can’t be discriminatory against people who for whatever reason people can’t have the vaccine, there might be medical reasons why people can’t have a vaccine.
“Or some people may generally refuse to have one, I think that’s mistaken, I think everybody should have a vaccine but we need to thrash all this out.
“In the interval (during the rollout of the vaccines) what I want to see is a proper review into the issue. That’s going to be led by Michael Gove, the Chancellor of the Duchy of Lancaster, who will be getting the best scientific, moral, philosophical, ethical viewpoints on it and will work out a way forward.
“The fervent libertarians will reject but other people will think there’s a case for it.”
What has been the political response?
Senior ministers have frequently appeared to dismiss the idea of introducing vaccine passports in the UK.
Nadhim Zahawi, the Government’s vaccines minister, initially labelled them “discriminatory” as ministers looked to persuade the public to take up the offer of a jab without the threat of being barred from entering hospitality or other venues if they do not get inoculated against Covid-19.
Conservative Mark Harper, the head of the Covid Recovery Group, says he opposes employers being allowed to demand staff get the vaccine.
Speaking on Question Time, he said that by not mandating a vaccine passport, but leaving it up to employers to insist on vaccination, would leave individuals with the burden of challenging discrimination in the courts.
He said the process would be discriminatory to groups such as pregnant women waiting until after giving birth to have a jab.
“The Government can’t just let (employers) get on with it,” he said.
“This needs to be debated in Parliament, the Government needs to put forward a proposal, we need to make a decision, then everyone knows where they stand rather than having this situation where people who have to have a jab sort out (challenging it) themselves.”
Mr Harper added that such a move would discriminate against young people who are needed to reboot the economy, but would be the last to get the jab.
However, former prime minister Tony Blair has, through his institute, regularly called for vaccine passports to be used to reopen society.
"The early evidence seems to be that if you’re vaccinated, you’re less likely to transmit the disease,” he said, adding that being able to show proof of inoculation in order to engage in certain activities is "just inevitable".
Are businesses likely to welcome Covid status certificates?
Some businesses are already seeking 'no jab, no job' contracts for workers, unless they have medical reasons not to have the vaccine.
London-based Pimlico Plumbers said when vaccinations are readily available, all new workers will have to have one, but boss Charlie Mullins insisted he would not force anyone to get the jab.
And Barchester Healthcare, which runs more than 200 care homes in the UK, has already announced all new recruits must be vaccinated unless they have a reasonable excuse.
"We look after the most vulnerable people in society," Chief Executive Dr Pete Calveley told Good Morning Britain. "It is a professional duty for doctors and I believe care workers to do their utmost to keep the residents and their colleagues and their families safe."
But he admitted he may lose approximately 1,000 workers as a result of the policy.
But Care Lead for Kepplegate Ltd, Adam Purnell said he would not introduce the policy as it would put pressure on the recruitment and retention of staff.
He said: "We've had a high uptake of staff having the vaccine but I reassured them that if they didn't their jobs would not be in jeopardy.
"Recruiting in health and social care is one of the most difficult things - we're underpaid, we're underfunded, we're undervalued. We're struggling to get people through the door to come and work in health and social care during a worldwide pandemic.
"So if we start enforcing and mandating vaccines on top of that, we're just going to limit the amount of people who are going to want to work for us."
Employment lawyer Amanda Lennon, Partner at Spencer West in London said that clients from different sectors have approached her for advice as they are keen to protect their staff and customers.
"Employers have a sound argument for a vaccine policy because the health and welfare of their staff and their customers is their responsibility.
"I work with a number of clients for various sectors and many of the employers are keen to have their staff vaccinated and have sought advice on how to go about it.
"One client, a charity that runs hostels for people in crisis, want all their staff to have the vaccine and the service users as a condition of having a place.
"That requires an overwhelming amount of planning to ensure they have the engagement with their employees and clients to work out the practicalities of how it could work effectively and where everyone is happy."
What are the legal issues associated with vaccine certificates?
Ms Lennon said that as the government has not mandated the vaccine - not made it legally compulsory - it is likely that it will be left up to individual firms.
"If employers are going to require employees to have the vaccine – effectively no jab no job – this brings with it legal risks," she said.
"People might have concerns for religious reasons or have underlying medical reasons including women who are trying to conceive and these are not things that employees necessarily want to disclose to employers," she said.
"Employers need to address the risk when requiring employees to have the vaccine – they can’t just force it on them."
She said it would be vital for employers to see it as an opportunity to consult employees and listen to their concerns.
She said: "Employers should take the initiative to be upfront with their employees and put themselves in their shoes when introducing a vaccine policy.
"The best employers understand their employees and go on a journey with them so that both parties are as comfortable as possible with any policy that is introduced."Philip Landau, an employment lawyer at Landau Law, said: "As the take-up of the vaccine among ethnic minorities is lower than average, then there may also be race discrimination if employers seek to roll out a universal requirement to for staff to provide a vaccine certification.
"Even if there is no discrimination, if employers force the issue and undermine the trust and confidence with staff who are unwilling or unable to supply the necessary certification, they could still face claims for unfair or constructive dismissal as long as they have two years’ service.
"An employment tribunal would then have to consider if it was reasonable for that employer to insist on a vaccine certificate."
What other issues will businesses have to consider?
Employers will also need to consider what their position is on agency staff, contractors and third parties in the workplace, Mr Landau said.
"Their position may be weaker in making a vaccine passport mandatory for their employees, but not universally applying the policy to third parties," he said.
"If employers do decide to roll out a new policy, they will need to introduce a new clause in the employees contracts of employment, and such a variation would require the consent of those employees.
"Enforcing such a change without consent would be a breach of contract which could entitle employees to resign and claim constructive dismissal."
Would vaccine certificates only affect new recruits?
Existing staff may have a stronger position, Ms Lennon said.
"For staff, to make any vaccine policy a condition of employment there would have to be an amendment to a contract negotiated with the employee whereas a new recruit may be required to agree to be vaccinated before a job is offered," she said.
"However, there are still the same legal risks associated with recruitment. If a candidate is refused the job because they do not want a vaccine on religious or health and safety grounds, they can still have a case for discrimination."
Could employees who refuse to get a vaccine face a disciplinary and lose their job?
Mr Landau said that he thinks that this could be a possibility.
He said: "I have seen many examples of businesses (who are doing their best to address health and safety concerns), insist that their staff be vaccinated or face disciplinary action.
"I imagine vaccination passports becoming the norm will put employers on a stronger footing both morally and legally to demand proof that their staff have had the jab.
"Whilst it may not ward off every legal claim that could wind its way to tribunal, it will go a long way to make employers more comfortable that they are doing the right thing."
However, the Confederation for British Industry (CBI) said that businesses should be focused more on testing employees rather than introducing domestic vaccine passports.
A spokesperson for the CBI said: "As the vaccine roll-out gathers pace, testing will still be an invaluable tool to stay on top of the virus and be especially useful for firms where people need to work in close proximity to help ensure a safer working environment for all.
"Workplace testing is gaining momentum but far more firms need to be encouraged. That’s where the business focus is right now, rather than clamouring for the introduction of a domestic vaccine passport."
What are the ethical concerns?
Campaign group Liberty warned that vaccine passports could create a “two-tier society”.
Head of policy and campaigns Sam Grant said: “Ministers have flip-flopped on the idea of immunity passports for months before quickly backing out again when faced with immense backlash.
“Renaming them ‘status certificates’ does nothing to address the fact that they would create a two-tier society where some people can access support and freedoms, while others are shut out – with the most marginalised among us hardest hit.”
What do unions say?
Unions have said that 'no jab, no job' vaccine policies are "legally questionable" and "self-defeating".
Unite said that it would "stoke a divisive, worker-blaming culture that glosses over the health and safety failings of bad employers" allowing them to "abdicate their responsibility in making workplaces Covid-secure.
The union said that forcing existing workers or new hires to be vaccinated has not been legally tested and "may leave employers open to discrimination lawsuits".
Unite assistant general secretary Howard Beckett said: "The 'no jab, no job' narrative is a disgraceful attempt to create a divisive narrative around workers and the vaccine.
“It is not workers who have risked lives through this crisis. Workers have kept the nations going through this crisis, putting their lives at risk and sadly on many occasions losing their lives. It is the decisions of Government that have cost lives through this crisis, not the actions of workers.”
UNISON said that that employer 'vaccine passports' are the wrong approach which could "put people's backs up".
Senior national care officer Gavin Edwards said: "Vaccine passports could be many months away. Employers' focus right now should be all about encouraging care staff to be vaccinated.
"Ensuring as many as possible take up the offer is key to restrictions easing and life returning to normal.
"That's why the government must get tough with employers threatening staff into having their jabs. All this does is put people's backs up.
"In a sector already struggling with thousands of vacancies this approach isn’t just plain wrong, it's self-defeating too."
What about customers? Will they be forced to show a vaccine passport to go to the pub, gym or theatre?
Although Vaccine minister Nadhim Zahawi MP initially dismissed the idea for vaccine passports to be required for entry into pubs, theatres or other venues, he later said it was "up to businesses to decide" whether or not to refuse entry to customers who had not been vaccinated.
However, for a sector that has been hit the hardest during the pandemic, the entertainment and hospitality sector do not seem particularly keen to force vaccine passports on customers.
A spokesperson for trade association UKHospitality said that its members are not supportive of the scheme.
“We do not believe that these are appropriate in a high street hospitality setting where we have already taken steps to mitigate risks," UKHospitality Chief Executive Kate Nicholls said.
She added: "Businesses have already put measures in place to ensure that venues are safe. They will be opening under tight restrictions and approaching the job of reopening with a wealth of experience from last year.
"In many cases, businesses have spent huge sums of money, changing layouts, overhauling staff training and ramping up cleaning regimes. This should be enough to ensure guests and staff are kept safe.
"We need to remember that hospitality is only linked to a tiny number of cases.
"Mandatory use of a vaccine passport will likely lead to headaches, place an extra burden on staff and cut revenue needlessly at a time when businesses cannot afford it.”
Meanwhile, West End venue owner Nica Burns told The Stage that theatres would find a way to "make things work".
She said: "We are very confident that we can make anything that fits with DCMS and for those who aren't vaccinated, we are happy to do rapid testing."
Phil Clapp, chief executive of the UK Cinema Association, said that vaccine passports for customers would cause "a range of practical and legal problems".
He added: "Making the proof of vaccination a condition of entry would open up cinemas to a host of possible claims for discrimination."
What are other countries doing?
Other countries are setting up vaccine passports to allow certain venues to reopen.
In Israel, people using gyms, hotels and synagogues require a 'green passport' on an app issued by the health ministry to prove they have been vaccinated.
People who have recovered from the virus and not eligible for the vaccine are able to obtain the certificate.
However, it is only valid for six months and is issued one week after the second dose.
Other European countries are issuing vaccine certification in different forms.
Estonia and Denmark are creating a digital certificate for people to prove they have had the jab.
Spain is compiling a database of vaccine refusers, which it will share with the European Union.
But health minister Salvador Illa said this will ensure no one has been accidentally missed off the vaccination list and will not be shared publicly or with employers.
In Greece, the prime minister has asked the European Commission to introduce certificates to allow "the freedom of movement of persons who have been vaccinated".
In response, Ursula von der Leyen, president of the European Union Commission, voiced support for creating a common EU-established vaccination certificate that can be issued by member states.