Talks on vaccine passports with foreign nations are ongoing, a foreign office minister has confirmed, as hopes rise in the UK for domestic holidays to soon be permitted.
James Cleverly, when asked about vaccine passports to allow for international travel, said the decision on who can enter a county is made by the respective government and ministers are "talking with our international partners to make sure that we coordinate with them".
He warned that taking a holiday in the UK is currently illegal due to coronavirus lockdown restrictions, and "that will only change when it's safe to do so based on the evidence".
But there are hopes that holidays within the UK could be allowed in the not too distant future after Welsh First Minister Mark Drakeford said his government was considering whether to allow holidays by Easter in self-contained accommodation.
Responding to the first minister's comments, Mr Cleverly said: "The government has been collecting data about the impact of the restrictions and the rollout of the vaccine.
James Cleverly on vaccine passports and domestic holidays:
"Those figures are looking promising, but really it would be inappropriate to speculate about what changes the prime minister was going to be announcing on Monday.
"We should remember that part of the reason why the figures are heading in the right direction is because we have been living with these restrictions - we don't want to release them too early, we don't want to go into another lockdown."
Vaccine passports to allow people to go on foreign holidays are "feasible", experts have said, but a lack of a set standards across countries means they cannot be introduced yet.
A report published on Friday in the Royal Society said more information is needed on the effectiveness of coronavirus vaccines in preventing infection and transmission, as well as duration of the protective immunity they provide, in order to establish how long a passport might be valid.
Professor Melinda Mills, director of the Leverhulme Centre for Demographic Science at the University of Oxford and a lead author of the report, said: "Understanding what a vaccine passport could be used for is a fundamental question - is it literally a passport to allow international travel or could it be used domestically to allow holders greater freedoms?
"The intended use will have significant implications across a wide range of legal and ethical issues that need to be fully explored and could inadvertently discriminate or exacerbate existing inequalities.
"International standardisation is one of the criteria we believe essential, but we have already seen some countries introducing vaccine certificates related to travel or linked to quarantine or attending events.
"We need a broader discussion about multiple aspects of a vaccine passport, from the science of immunity through to data privacy, technical challenges and the ethics and legality of how it might be used."
On Monday, Boris Johnson will reveal his roadmap out of lockdown, in which he is expected to set out dates for the reopening of society, with schools to come first and hospitality to go last.
On the roadmap, Mr Clevery said Covid-19 vaccines "seem to be having a positive effect" on transmission of the virus, with more than 1 in 4 of all adults having received a first jab.
"What that means in terms of easing lockdowns and getting back to normality, we will have to assess that."
Cleverly on Boris Johnson's lockdown roadmap:
He added: "The prime minister will be making a statement about that on Monday and we shouldn't really guess or speculate because the decisions will be made based on the scientific evidence."
First Minister Drakeford said "detailed discussions" will be held with the Welsh tourism taskforce over the next two weeks following a meeting on Thursday, looking at whether "there's anything that we might be able to do around the Easter period".
He told the BBC: "The most that would be would be the reopening of self-contained accommodation where there aren't shared facilities and there isn't social mixing.
"But if we could do that - and six weeks is a very long time in this business - if we could do that in six weeks' time, I know that that would be a boost to the industry and a big boost to hundreds of thousands of families in Wales for whom going down the caravan for a few days or a break would be a very welcome prospect."
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