Boris Johnson has vowed to “absolutely ruthless” in deciding whether to bring in quarantine rules for holidaymakers travelling back from France.
Officials are looking at whether to add France to the list of destinations where tourists must isolate for 14 days on returning to the UK – with a decision expected as soon as tonight.
Coronavirus rates in France have been on the rise, with more than 2,500 cases recorded on Wednesday – the highest since the country eased its lockdown.
Ministers are considering whether the scrap the travel corridor to the popular holiday destination, which could affect thousands of British tourists.
Quarantine restrictions for Malta and the Netherlands – which both have higher infection rates than France – are also reportedly being considered.
“We have got to be absolutely ruthless about this, even with our closest and dearest friends and partners. I think everybody understands that,” Mr Johnson said on a visit to Northern Ireland.
“We will be looking at the data a bit later on this afternoon – looking exactly where France and other countries are getting to.
“We can’t be remotely complacent about our own situation. Everybody understands that in a pandemic you don’t allow our population to be reinfected or the disease to come back in.
“That is why the quarantine measures are very important and we have to apply them in very strict way.”
A formal announcement could come as early as tonight on which countries are being added and removed from the list.
It comes weeks after quarantine rules were abruptly changed for Spain, causing chaos for tourists and the travel industry.
Luxembourg was also added to the list after a spike in cases, followed by Belgium, Andorra and the Bahamas.
But restrictions were lifted on countries including Brunei and Malaysia.
No10 has warned the public that “no travel is risk free” during the pandemic and other countries could be added to the quarantine list at short notice.
People who flout quarantine rules can be fined up to £1000 in England.