Norway and Denmark on Monday temporarily banned flights from Britain, joining a host of countries stopping UK travel over a new strain of the novel coronavirus.
Both countries said the ban was for an initial period of 48 hours.
"We have to ensure that the virus variant that has been detected in Britain spreads to Norway as little as possible," Norway's Health Minister Bent Hoie said.
"That's why we are now stopping direct flights from Britain and tightening restrictions for travellers from this area," he added.
In addition to the flight suspension and the 10-day quarantine already imposed on people arriving from abroad, travellers from the UK will until January 10 have to undergo tests and register with the authorities.
Those who arrived within the last 14 days were also told report to local authorities and get tested.
Denmark, which has already confirmed nine cases of the new strain, however did not announce any additional restrictions on travellers from the UK.
"Denmark faces a very serious situation," Transport Minister Benny Engelbrecht said.
"The mutated Covid-19-virus, that quickly has spread out in London and other parts of England, can according to health authorities make it harder to control the infection."
Nordic neighbours Sweden and Finland both announced travel bans from the UK over the weekend.
Finland's went into effect at midday (1000 GMT) on Monday and Sweden's Home Minister Mikael Damberg said the government would formally announce the travel ban sometime on Monday.
Many countries around Europe and elsewhere have also suspended UK flights following the outbreak of a variant of the virus that is reportedly up to 70 per cent more contagious.
According to the World Health Organization (WHO) there is currently "no evidence to indicate any change in disease severity."