Governments have taken steps to tighten their borders as cases of the Omicron variant of coronavirus appeared in countries on opposite sides of the world.
Japan was the latest to take action as it said it will suspend the entry of all foreign visitors from around the world as the variant spreads.
The decision means Japan will restore border controls it eased earlier this month for short-term business visitors, foreign students and workers.
READ MORE: Spain update travel restrictions for unvaccinated British tourists
Many countries have moved to tighten their borders even as scientists warned it is not clear if the new variant is more alarming than other versions of the virus.
The variant was identified days ago by researchers in South Africa, and much is still not known about it, including whether it is more contagious, more likely to cause serious illness or more able to evade the protection of vaccines.
But many countries rushed to act, reflecting anxiety about anything that could prolong the pandemic that has killed more than five million people.
Israel decided to bar entry to foreigners, and Morocco said it would suspend all incoming flights for two weeks starting on Monday - among the most drastic of a growing raft of travel curbs being imposed by nations around the world as they scrambled to slow the variant's spread.
Noting the variant has already been detected in many countries and that closing borders often has limited effect, the World Health Organisation (WHO) called for frontiers to remain open.
The US plans to ban travel from South Africa and seven other southern African countries starting from Monday.
Many countries are introducing such bans, though they go against the advice of the WHO, which has warned against over-reaction before the variant is thoroughly studied.
In Europe, much of which already has been struggling recently with a sharp increase in cases, officials were on guard.
Over the weekend, health authorities in the UK found three cases of the variant, which prompted the British government to tighten rules on mask-wearing and testing of arrivals in the country.
Spain announced it will not admit unvaccinated British visitors starting from December 1.
Italy was going through lists of airline passengers who arrived in the past two weeks.
France is continuing to push vaccinations and booster shots.
Despite the global worry, some countries are continuing with previous plans to loosen restrictions, with signs of reopening in Malaysia, Singapore and New Zealand.
Malaysians working in Singapore held joyful reunions with loved ones after returning to their homeland following the partial reopening of a land border that was closed for nearly two years because of the pandemic.
Here's the latest advice from the Foreign Office:
Austria is currently in a nationwide lockdown and hotels are closed to tourists
If you are fully vaccinated with a vaccination approved for use in the EU, you are exempt from quarantine on arrival in Poland, but must present evidence of your COVID-19 vaccination at the border and 14 days must have passed since your final dose.
Arrivals from the UK must have proof of vaccination and proof of a negative COVID-19 test result to enter Switzerland, and self-quarantine for 10 days.
The Spanish government requires all arrivals to Spain from the UK to present on entry a Health Control Form and proof of vaccination from December 1.
The UK is currently on France’s amber list.
Travellers who are fully vaccinated do not need an essential reason to travel to France and do not need to self-isolate on arrival.
Fully vaccinated travellers no longer need to present evidence of a negative test result before travel.
UAE (Dubai and Abu Dhabi)
Residents, tourists and visitors travelling from or through the UK and arriving in Dubai and Abu Dhabi must have a negative COVID-19 PCR test before departure and present the certificate at check in.
These need to be taken no more than 72 hours prior to departure for arrivals to Dubai and no more than 48 hours prior to departure for arrivals to Abu Dhabi.
Travellers arriving in Abu Dhabi will also be required to undertake a COVID-19 PCR test on arrival.
Travellers arriving in Dubai may be required to undertake a further COVID-19 PCR test on arrival and will have to isolate pending the result of the COVID-19 PCR test.
Fully vaccinated travellers do not have to quarantine but are recommended to take a viral test within 3 to 5 days of arrival in the US.
Travellers who have not been fully vaccinated and are allowed to travel to the USA through an exception must take a test within 3 to 5 days after arrival in the US, self-quarantine for 7 days after arrival in the US, even if you test negative, unless you have an exception and become fully vaccinated, if staying 60 days or longer.
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