People coming to the UK from France and the Netherlands will be forced to quarantine for 14 days from Saturday the government has announced.
Transport Secretary Grant Shapps announced the move just hours after the prime minister said his government would be "absolutely ruthless" in deciding whether to impose the restriction.
Malta and the Netherlands have also been added to the list, and holidaymakers with plans to visit these countries, face two weeks in self-isolation when they return.
The decision is a blow in particular for the French tourist industry, as well as holidaymakers from UK who are already across the channel or have trips booked in coming weeks.
Clement Beaune, France's secretary of state for European affairs, tweeted that the UK's decision was a matter of "regret" for the French.
Transport Secretary Grant Shapps said the decision was triggered when the rate of infection in the affected countries exceeded 20 cases per 100,000 people.
Outbound travellers are warned against going to any of the countries because they presenting an “unacceptably high risk” to British citizens.
Nick Thomas-Symonds, the shadow home secretary, said: “While we support evidence-based measures at the border, it’s vital that the government has a joined-up strategy, and recognises the impact of this on travel-related businesses. It is vital that a sector-specific deal is put in place urgently.
The MP added: "That the government has still not put in place an effective track, trace and isolate system has made matters far worse and made it more likely that we are reliant on the blunt tool of 14-day quarantine."
According to the data company Statista, people from the UK paid 10.35 million visits to France last year, putting it second behind Spain - with 18.12 million - in terms of popularity.
There are at least 500,000 British holidaymakers in France at present, plus hundreds of thousands other UK citizens who are semi-permanent residents.
Amsterdam, is the main attraction in the Netherlands. The country's beaches and canal network are popular with UK families. Approximately 50,000 British holidaymakers and a number of business travellers are estimated to be in the Netherlands.
Ahead of a government meeting on the new measures, UK Prime Minister Boris Johnson said: "We can't be remotely complacent about our own situation. Everybody understands that in a pandemic you don't allow our population to be re-infected or the disease to come back in."
On Thursday, France reported 2,524 new coronavirus cases in 24 hours, the highest daily increase since its lockdown was lifted in May.
The country's Prime Minister, Jean Castex, said on Tuesday that coronavirus numbers had been going "the wrong way" for a fortnight.
The Netherlands had a rate of 40.2 per 100,000 over 14 days, and Malta had a rate of 74.8 per 100,000.
Meanwhile, Ferries are operating at reduced capacity through social distancing. Eurostar is also running a reduced service.
Seats on the British Airways flight from Paris CDG to Heathrow on Friday quadrupled in price after the government's announcement.
Elsewhere, the government has announced that maximum fines for people in England who repeatedly refuse to wear a face covering could double to £3,200, while organisers of illegal raves could face a £10,000 penalty.