Dozens of countries around the world have imposed travel bans on Britain, where a more infectious variant of the coronavirus has gained a foothold, stranding passengers at airports and generating queues on motorways after France shut its border.
India, Pakistan, Saudi Arabia, Hong Kong and Canada, along with a host of European nations, joined the growing list of countries restricting travel with Britain in the hope of preventing the variant's arrival.
British experts say the new strain is 70 per cent more transmissible, with London and the south-east of England especially hard hit.
Yet the World Health Organization said on Monday that the new virus strain is controllable.
"This situation is not out of control but it cannot be left to its own devices," WHO health emergencies chief Mike Ryan told a press conference in Geneva, urging countries to implement tried-and-tested health measures.
According to the WHO, people who catch the new variant infect 1.5 other people on average, compared to a reproduction rate of 1.1 for previously known variants in Britain.
There is also a widespread consensus among virologists that COVID-19 vaccines would be effective against the variant.
The head of German company BioNTech, Ugur Sahin, told DPA the company has already tested the vaccine against 20 other virus variants and saw a successful immune response that deactivated the virus.
The new variant is a stronger mutation and the vaccine will be tested against it over the next two weeks, Sahin said.
British scientists are still trying to find out how much of this increase is due to changes in the virus, and how much is related to behavioural factors among the population, the WHO's chief Covid-19 scientist Maria Van Kerkhove said.
There is no evidence so far that the new strain causes more severe or deadly diseases, she stressed.
The variant found in Britain has also been seen in single individuals in Australia, Iceland, Italy and the Netherlands, as well as a few cases in Denmark, the WHO said.
The European Union was trying to work toward a coordinated response amid a flurry of travel restrictions announced separately by the bloc's 27 countries.
In a meeting under the umbrella of the EU's Integrated Political Crisis Response mechanism (IPCR), delegates "stated their support for rapid action towards a coordinated EU approach in relation to measures applied to connections with the UK ... and called for guidelines from the Commission," an EU official told dpa.
"Given the experience at the beginning of the pandemic, member states also stressed the importance of keeping the borders open within the Schengen area," the official said, referring to Europe's passport-free travel zone.
