The UK is imposing a two-week quarantine on travellers from Denmark, following an outbreak of a rare mutation of COVID-19 in the Nordic country's mink farms.

"I have taken the swift decision to urgently remove Denmark from the government's travel corridor list as a precautionary measure given recent developments," UK Transport Secretary Grant Shapps said in a statement.

Denmark said earlier this week it had found a "unique" mutation of the virus that has the potential to derail work on developing a vaccine. Health officials in the country are coordinating their efforts to contain the outbreak with the World Health Organisation, which includes culling the entire population of mink, or up to 17 million animals.

At a briefing late on Thursday, Danish Health Minister Magnus Heunicke said the COVID-19 mutation, which originated in the western peninsula of Jutland, has now also been identified in at least one person in the country's east, closer to the capital Copenhagen.

Danish health officials say they know of 12 people who have been infected with the new virus. On Friday, local media reported that over 200 people have contracted various forms of coronavirus mutations stemming from mink, 14 of whom were outside the region in which the mutation originated.