Japanese citizens and foreign residents can still enter, but are required to self-quarantine for 14 days, according to Japanese public broadcaster NHK.
The move comes after the Tokyo metropolitan government on Saturday confirmed two new cases of the Covid-19 variant involving people who have recently returned from the UK.
The two new cases were the first to be discovered outside the country’s airport quarantine.
On Friday, five other passengers from Great Britain were detected with the variant at the Japanese international airports.
Restrictions of varying degrees have been announced by countries such as Denmark, Ecuador, Greece, Portugal, Spain and Ukraine. Others have banned travel or suspended flights from the United Kingdom, such as Argentina, Belgium, Brazil, Canada, China, Colombia, Germany, India, Italy, the Netherlands, Russia and Spain.
Others have extended travel bans or restrictions to other countries where the variant has been detected, such as Denmark, the Netherlands and Australia. A number of countries have also imposed restrictions on travel from South Africa, where a different option has been reported, according to Maria van Kerkhove of the World Health Organization.