GPS tracking could be used as an alternative to hotel quarantine, UK government scientists have suggested.
The Scientific Advisory Group on Emergencies (Sage) suggested “electronic monitoring” could force more people to self-isolate at home after returning from overseas.
The alternative measure was proposed amid mounting anger that ministers had failed to ban travellers from 35 countries with new variants of the coronavirus.
The UAE is among 33 countries on the UK government's so-called 'red list' where non-citizens are prevented from travelling to Britain owing to concerns over mutant strains which could evade vaccines, particularly the Oxford/AstraZeneca vaccine.
However, a World Health Organisation study found there were dozens of other countries where the South African and Brazilian variants are present.
The WHO said the South African variant had spread to 41 countries, 29 of which do not feature on the UK’s red list. The Brazilian variant was identified in 10, but a travel ban is not in place for six.
Austria, Belgium, Canada, Denmark, France, Greece, Japan, Kenya, Norway, Sweden, Switzerland and the US are among the countries that do not feature on the UK’s list.
The opposition Labour party said the WHO’s study showed the UK’s current quarantine measures left the country “completely exposed”.
“Not only are the measures far too slow to begin, they are also dangerously inadequate,” Shadow Home Secretary Nick Thomas-Symonds said.
Vaccines Minister Nadhim Zahawi said hotel quarantine was only one part of the UK's border measures.
“The really important part is the passenger locator form, which allows us to know exactly where you’re staying and … the pre-departure testing which we’ve introduced,” he told Sky News.
But scientists said all quarantine measures were dependent on people adhering to self-isolation rules.
The Sage group said that as well as making people stay in hotels “digital methods” could be used to enforce quarantine, but admitted such a policy presented challenges.
International travellers arriving in Abu Dhabi, for example, have to wear a tracking device while they complete a mandatory 14-day home quarantine.
In Poland, returning travellers are required to download a mobile app which prompts users to send a selfie instead of a police check-up.
The photo is compared with pre-submitted images and its geolocation data is analysed to determine whether the user is at home. Failure to respond to the check-in notification within 20 minutes notifies police.
However, the app has been criticised for technical issues and concerns over privacy and data protection.
There is also concern it may be too late to strengthen quarantine measures as the new variants will inevitably spread in the UK.
Dr Mike Tildesley from the University of Warwick said authorities might have been too slow to contain the South African strain.
"Sadly we may be in a similar situation to the Kent variant, which started in the south-east but eventually spread across the whole country," he told BBC's Radio 4 Today programme.