A cabinet minister has said people shouldn't be booking a holiday even if it is in the UK.
Transport secretary Grant Shapps told the BBC that “people shouldn’t be booking holidays right now – not domestically or internationally” adding it was "too soon" to give people the green light.
Boris Johnson is due to give more details about how he plans to take the country out of lockdown on 22 February, although it is unknown whether this will include travel advice.
Shapps, speaking on BBC Radio 4's Today programme on Wednesday, said: “We don’t know yet whether that [Johnson's update] will include information on things like holidays, simply because we don’t know where we’ll be up to in terms of the decline in cases, deaths, vaccination.
“And not just the vaccination programme here, but the vaccination programme internationally, because people will be going outside of our borders."
Watch: It is 'too soon' to book a summer holiday, says Transport Secretary Grant Shapps
Shapps indicated that travel restrictions may not be eased until everyone in the UK – and potentially in overseas destinations – has had their coronavirus vaccinations.
Asked what needs to change for travel restrictions to be lifted, he replied: “First of all, everybody having their vaccinations.”
Pressed on whether the rules will remain in place until that happens, he said “yes”, before explaining that Boris Johnson will set out a “road map” for relaxing lockdown measures on February 22.
A spokesperson for travel association ABTA responded: "You can book a summer holiday now with confidence by booking a package holiday through an ABTA member, and many travel companies are also offering additional flexibility to take into account the uncertainty created by the pandemic.
“If we wait for the full rollout of the vaccination programme in the UK before people start to travel overseas, we’ll lose another summer season to the pandemic – something the travel industry can’t afford."
The transport secretary's comments mark a distinct toughening in rhetoric around holiday advice in recent days and weeks.
Last week, both Boris Johnson and Matt Hancock said they were "optimistic" people would be able to enjoy a "great British summer".
Johnson said: "I don't want to give too much concrete by way of dates for our summer holidays. I am optimistic - I understand the reasons for being optimistic - but some things have got to go right.
In December, Hancock revealed he had already booked a staycation his Cornwall.
On Monday, Professor Jonathan Van-Tam, deputy chief medical officer for England, warnedit was too early to say whether Brits should be making holiday plans.
He said any easing of lockdown restrictions in England would have to take place “gradually” and that contemplating what will happen in summer is stepping into the realm of a guessing game.
He added: “Public health counter measures, non-pharmaceutical interventions, social distancing restrictions, they will have to be released gradually.
“How quickly they can be released will depend upon three things – the virus, the vaccine and the extent to which the public obey the rules that are in place, which thankfully the vast majority always do.”
He said it was too soon to say to what extent people could begin to start planning summer holidays warning that "the more elaborate your plans are for summer holidays" the more likely it would be that they could be impacted.
At Wednesday evening's Downing Street press conference, meanwhile, Johnson refused to address the matter, saying: "It’s just too early for people to be certain about what we’ll be able to do this summer and we hope to be able to say more in the week of the 22nd.
"I understand why people want to make plans now but we’re just going to have to be a little bit more patient."
Under the current coroanvirus lockdown rules, all leisure travel is banned in the UK.
However, tour operators say there is huge pent-up demand and are selling trips from as early as April onwards. They are desperate for bookings after suffering huge losses during the pandemic.
It is not known whether existing restrictions on essential travel – such as for work or family emergencies – will continue once holidays can resume.
Currently, arriving travellers must take a negative coronavirus test within 72 hours of their journey to the UK.
They must also self-isolate for 10 days, or until they have received a negative result from a test taken after at least five days.
From Monday, arriving passengers will also be required to take coronavirus tests on the second and eighth day after they enter the UK.
Travellers from the 33 “red list” countries arriving in England will be sent to a quarantine hotel for 10 days from Monday, costing £1,750.
Airline trade body the International Air Transport Association has said it is in talks with the government about developing an app allowing travellers to share their coronavirus test and vaccination status.
Mr Shapps said he has been in discussions with counterparts in Singapore and the US about the possibility of an international certification system.
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