UK Home Secretary Priti Patel described the new strain of Covid-19 sweeping across Britain as “bouncy”.
She told Sky News: “This new strain of coronavirus is a stronger strain of the virus in the sense it’s more transmittable. It’s a bouncy virus.”
Ms Patel said the government would not hesitate to take stronger measures if case numbers continue to rise.
The new strain is up to 70 per cent more infectious and led the British government at the weekend to introduce tighter restrictions on London and surrounding areas.
European states, Canada, Kuwait, Israel, India, Russia, Saudi Arabia and Turkey are among those banning flights from the UK to try to stop its spread. An EU agency reported, however, that at least three other European countries have recorded cases of the new mutation.
UK opposition leader Sir Keir Starmer said on Monday the spread of a new strain of the coronavirus was “out of control”.
Chief scientific officer Sir Patrick Vallance said on Monday that the new strain was being seen in different parts of the UK.
“We know there are cases everywhere, it’s not as though we can stop this getting into other places,” he said.
The UK recorded a further 33,364 COVID-19 cases on Monday and 215 deaths of people who had tested positive for the virus within 28 days.
That compares with 35,928 cases announced on Sunday and 326 deaths.
Ms Patel gave an update on the situation regarding the border chaos that struck the UK since the new virus strain emerged. She said the government is working with France in an attempt to find a way to lift border closures snarling one of Europe's most important trade routes just days before the Brexit cut-off.
She said food in Britain is plentiful and shoppers should not be concerned about supermarkets running out of supplies.
On Monday, Britain's two biggest supermarket groups, Tesco and Sainsbury's, said that gaps will start to appear on British supermarket shelves within days if transport ties with mainland Europe were not quickly restored.
But Ms Patel played down those concerns.
"I don't think anybody should be worried – there is plenty of food in our shops," Ms Patel told LBC.
Much of the world closed borders to the UK in recent days after London identified a highly infectious new coronavirus strain, leaving hundreds of lorry drivers stranded in southern England.
France shut its border to arrivals of people and lorries from Britain. The BBC cited French Europe Minister Clement Beaune as saying that Britain and France would announce a deal to restart freight by Wednesday.
"We speak to our colleagues in France constantly on a range of issues and that work has been under way over the last 24 hours and we'll continue today," Ms Patel told Sky.
Asked if there would be a resolution today, Ms Patel said: "We're working to get a resolution. It's in both our interests to ensure that we have flow.
"We'll see what materialises today," Ms Patel said.
The discovery of the new strain, mere months before vaccines are expected to be widely available, sowed new panic in a pandemic that has killed about 1.7 million people worldwide and more than 67,000 in Britain.
With the UK in effective Covid quarantine nine days before it is due to end informal EU membership, some shoppers stripped shelves in supermarkets.
As financial markets tumbled, stranded lorry drivers near the port of Dover said they just wanted to get back home in time for Christmas.