Mike Tildesley, a member of the government’s Scientific Pandemic Influenza Group on Modelling, which reports to the government’s Scientific Advisory Group for Emergencies (Sage), told BBC Radio 4’s Today programme on Saturday (20 March) there was a danger holidaymakers could import new variants resistant to current vaccines.

"I think international travel this summer is, for the average holidaymaker, sadly I think, extremely unlikely," said Tildesley. "I think we are running a real risk if we do start to have lots of people going overseas in July, for instance, and August because of the potential for bringing more of these new variants back into the country.

"What is really dangerous is if we jeopardise our vaccination campaign by having these variants, where the vaccines don’t work as effectively, spreading more rapidly."

Transport secretary Grant Shapps reiterated it was "too early to tell" when overseas holidays would be allowed. The government is currently working to an "at the very earliest" 17 May date for a resumption of international travel, pending a review by the Global Travel Taskforce due on 12 April.

More than half of all UK adults have now received their first dose of a Covid-19 vaccine, health secretary Matt Hancock said on Friday (19 March), with new records set at the weekend for the number of doses administered in a single day.

Hancock said people must be patient and vigilant, stressing the taskforce would make a judgement on how travel could be restarted safely and when, adding it would work with the industry to do so. "That’s a judgement that we should make in a few weeks time, not now," he told Sky News.

Sage’s professor Andrew Hayward, meanwhile, told Times Radio the fresh wave of Covid infection in mainland Europe, which has forced France, Italy, Germany and Poland to take new protective action, was also a concern, with incidence of the South African variant of Covid-19 increasing.

On Sunday (21 March), another Sage member – professor Kamlesh Khunti – said he did not think people should be planning overseas summer holidays until 2022. "

We cannot jeopardise this now," The Guardian reports him as saying. "Our rates are coming down, our vaccination [rate] is fantastic. The biggest fear we have is new variants that vaccines don’t work as well against."

Another advisor to Sage, professor Rowland Kao, said there were reasons to be cautious about restarting travel, including the risk posed by vaccine-resistant variants.

Speaking to the BBC’s Andrew Marr Show on Sunday, defence secretary Ben Wallace said an extension to the current ban on overseas leisure travel couldn’t be ruled out and that booking a trip for the summer would be "premature". 

"We are not going to do anything that puts at risk this national effort to control this pandemic," said Wallace.

Speaking to Sky News the same morning, Wallace added that ministers and the country "could not be deaf and blind to what’s going on outside the UK," alluding to new variants and the incidence of fresh Covid infection in Europe.

‘Premature comments’

Huw Merriman, chair of the government’s transport select committee, urged ministers to consider the likely impact of another setback for overseas leisure travel on the UK’s outbound travel sector.

"[The] UK vaccination programme is going well; we must continue with 12 April international travel plan for 17 May unlock," Merriman tweeted on Saturday, citing the BBC’s report of Mike Tildesley’s comments. "We cannot shut ourselves away forever or doom our travel industry and workforce."

Julia Lo Bue-Said, chief executive of the Advantage Travel Partnership, said: "Casting doubt on summer holidays now some three weeks ahead of when the Global Travel Taskforce are set to make their recommendations is unnecessary.

"Meetings have involved industry, I was there alongside others, so why has an advisor to Sage not fed into GTT [the taskforce] instead of the press? Premature comments ahead of the summer damage confidence and are unnecessary."

Tim Alderslade, chief executive of Airlines UK, the trade body for UK registered airlines, added: "It is too early to say what the state of Covid will be in Europe and globally in 10 weeks’ time.

"Our focus between now and then must be working with ministers on a framework for travel that is robust and workable, and can stand the test of time as we enter the all-important summer period.

"We have always said any reopening must be risk-based, but also led by the overriding assumption that as the vaccine roll-out accelerates both here and abroad, a phased easing of restrictions is achievable.

"We know that universal, restriction-free travel is unlikely from 17 May but under a tiered system, based on risk, international travel can meaningfully restart and build up, with minimal restrictions in time."