Brits returning home from Croatia, Austria, Trinidad and Tobago must self-isolate for 14 days from Saturday.
The countries were stripped from the ‘safe list’ following fears that that the rate of infection was too high.
They joined popular destinations France and Spain – in a further blow to holidaymakers.
The Netherlands, Monaco, Malta, Turks & Caicos and the island of Aruba were also previously added to the quarantine list.
But in better news, Portugal was removed from the quarantine list, meaning Brits can now travel there freely without any restrictions.
We’ve searched out some of the best last-minute Portugal holiday deals for both August and September if you fancy a trip.
The new measures, which are set to affect thousands of holidaymakers at risk, begin at 4am on Saturday.
Croatia currently has 30 cases per 100,000 people according to the latest figures from the European Centre for Disease Prevention and Control.
The number of cases in Trinidad and Tobago cases has surged in the last month, with a sharp 232 per cent spike in the number of cases per 100,000 people between August 12 and 19.
In Austria, the rate of cases per 100,000 has increased from 10.5 on August 13 to 20.3 on August 20, an increase of 93pc, forcing officials to strike the country from the list.
Are you on holiday in any of the affected countries at the moment or due to fly out? Email us at [email protected]
The Foreign and Commonwealth Office (FCO) is not advising holidaymakers who are already in the affected countries to leave.
But it is now advising British nationals against “all but essential travel” to them.
The Association of British Insurers (ABI) has previously confirmed that holidaymakers travel insurance will remain valid for people who are already in the affected countries until they return home.
Here’s the latest travel advice from each airline.
The airline has confirmed that they will continue to fly to Croatia and Austria despite the change in government advice.
But customers who no longer wish to travel can transfer their flights without a change fee or receive a voucher for the value of the booking
All package holidays were already cancelled until the end of August and a spokeswoman says the airline are keeping a close eye on restrictions.
Customers set to visit Croatia in Septemberwith easyJet holidays can change their holiday option without incurring any fees.
A spokeswoman said: “Currently holidays to Portugal and Croatia aren’t due to start for easyJet holidays customers until 1 September at the earliest and even later for Austria.
“We will be reviewing our Portugal programme and contacting those customers with booked holidays to share the good news that they can go ahead.
“We continue to monitor the situation closely for all of the destinations we offer on a rolling basis and will be contacting customers with Croatia bookings due to travel in September to discuss their options.
“This includes an option of cancelling their holiday for credit without incurring any fees to be put towards a future or alternative booking with us.”
The airline is restarting flights to Portugal on August 24, but has not yet made an announcement about Croatia.
This morning, the tour operator announced that thousands more flights to Faro would be available, following “strong customer demand”.
Flights are available from Birmingham, East Midlands, Edinburgh, Glasgow, Leeds Bradford, London Stansted and Manchester.
Steve Heapy, CEO of Jet2.com and Jet2holidays said: “We welcome this change in government advice which means that customers can once again look forward to enjoying their well-deserved holidays in the stunning Algarve region.
“With flights and holidays operating to Faro, in addition to Madeira, we are thrilled to be offering customers two fantastic options in Portugal when they’re looking to book their well-deserved holiday away from the gloom.”
The Irish airline is set to continue its flights to Croatia and Austria.
A spokesman said: “Passengers who do not wish to travel on their booked flight can move it to another date, in which case, a flight change fee and the difference in fare may apply.
“We call on the UK Govt to take immediate action and to drop this ineffective quarantine in place of a more coherent and science based approach to international travel like improved testing, contact tracing and rapid tests at airports”.
The airline is resuming flights to Portugal on August 29.
A spokewoman said: “We’re really pleased the Government has confirmed British travellers will be able to holiday to Portugal without the need to quarantine on their return to the UK.
“In line with the latest advice, we will be resuming flights to Portugal from 29 August.”