In addition, the Foreign Office says Spain poses “an unacceptably high risk for British travellers,” and now advises against all non-essential travel to the whole country, including the Balearic and Canary Islands.
Travel insurance for British holidaymakers already in Spain will remain in effect; UK travellers in Spain are not being advised to leave.
But anyone travelling to the mainland against Foreign Office advice will find their policy is invalid.
The sudden moves, in response to several spikes of coronavirus infection in Aragon, Navarra and Catalonia, will affect several hundred thousand British people currently on holiday there.
A further two million people are estimated to be booked to travel from the UK to Spain in the next month alone; it is by far the most popular destination for British holidaymakers.
These are the key questions and answers.
What has changed?
On 8 June the UK government imposed a blanket requirement for all incoming travellers by air, sea and rail to self-isolate for two weeks. This was lifted for dozens of countries, including Spain, on 10 July.
But 16 days after England, Wales and Northern Ireland removed the quarantine requirement from Spain (and just a few days after Scotland did the same), the obligation has been reimposed.
For British holidaymakers currently in Spain, it was shocking news. When they set off, they were not expecting to have to quarantine on their return.
But they are now learning that they must go home from the airport or sea port and stay there for two weeks.
What exactly does quarantine involve?
Arriving travellers are required to go direct to their home or to other suitable accommodation. They may do so by public transport.
The “quarantinee” must immediately self-isolate for 14 days, timed from the day following their arrival.
A holidaymaker who flew out to Spain for a week’s holiday on the last no-quarantine day, 25 July, will return on 1 August.
Their self-isolation must begin immediately, but the clock starts ticking only on 2 August – and so the first time they will be able to venture out is immediately after midnight on 16 August.
Meanwhile they can leave home only for medical assistance, to attend court or a funeral – or to go shopping for essentials if there is no one else who can supply provisions.
Leaving home for work, exercise, socialising or walking the dog is not permitted.
But I am a key worker and must return to my job the day after my return. Surely I am exempt?
Almost certainly not. Most of the exemptions are very narrowly defined and cover either transport professionals or key workers travelling from abroad to the UK specifically on government business. Holidays do not count.
What about important family obligations?
You will not be able to leave your house to meet any such commitments during quarantine, unless they involve a court case or, heaven forbid, a funeral,
Can I shorten quarantine by taking a coronavirus test?
No. Unlike some other countries, there is currently no test alternative to UK quarantine – though Heathrow airport and others are pushing for a system involving a sequence of tests that could approximately halve the length of self-isolation.
I have a package holiday booked for August. What are my rights?
Package holidays to Spain will not operate because the Foreign Office regards the area as too dangerous.
Tui cancelled departures on Sunday morning, 26 July, but the aircraft took off anyway to collect passengers from Spain.
Travellers with holidays to mainland Spain up until 17 August have had their trips cancelled, while all packages to the Balearics and Canary Islands are off until 10 August.
“All customers currently on holiday can continue to enjoy their holiday and will return on their intended flight home,” Tui said.
People whose packages are cancelled will be entitled to a full refund, but can choose an alternative holiday or a voucher for future travel if they prefer.
Under the Package Travel Regulations, people whose trips are cancelled should get their money back within two weeks, but that time limit is unlikely to be met given the extreme stress on the travel industry.
I have booked a “DIY” trip, with flights, accommodation and car rental all booked separately. Can I get my money back?
It will be difficult. Despite the sudden quarantine decision, there is every chance that your flight will still be operating. After all, there are plenty of people who will be expecting to be flown home from Spain, and so many outbound flights will be running.
If the departure goes ahead as planned, the airline is legally entitled to refuse a refund even though you have compelling reasons not to go – such as work or family commitments.
However, easyJet has said that it will offer options to passengers booked to Spain in the near future, enabling them to switch journeys or take a voucher.
Britain’s biggest budget airline tweeted: “We are monitoring the situation and continue to provide some flexibility for those who, if they no longer wish to travel, can transfer flights without a change fee or receive a voucher for the value of their booking.
“We plan to operate our full schedule in the coming days.”
British Airways said: “Customers who decide they no longer wish to travel are able to claim a voucher for future travel.”
A Ryanair spokesperson told The Independent: “For non-cancelled flights, standard T&Cs apply.
“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.”
While new bookings until September offer no flight-change fee flexibility, for other booking this is £35 to £95 per flight.
Any accommodation or car-rental flexibility will depend on the deal you agreed with the supplier, and their attitude. They may be prepared to allow you to postpone – but are unlikely to offer you any cash back.
If you have a good insurance policy issued before mid-March, you may be able to claim for unavoidable losses.
Can I dodge quarantine by returning from Spain via France, Gibraltar or another third country?
No. Every traveller to the UK must complete a passenger locator form, in which they are expected to spell out the countries they have visited in the past two weeks.
What if I have another foreign trip due to depart before my 14 days of quarantine are up?
You can go directly from your place of self-isolation to the airport, sea port or international railway station, and leave the country. Indeed, the only way to reduce the length of quarantine is to go abroad again.
The English law is here (Wales, Scotland and Northern Ireland have near-identical Statutory Instruments.) It says you must self-isolate until whichever is the earlier of (a) the end of the 14th day after the day of arrival or (b) departure from England.
It adds: “During the period of their self-isolation [a person] may not leave, or be outside of, the place where [they are] self-isolating except to travel in order to leave England, provided that they do so directly.”
Regrettably, the government online guidance is misleading. It says: “When you arrive in the UK, you will not be allowed to leave the place where you’re staying for the first 14 days you’re in the UK (known as ‘self-isolating’) unless you’re arriving from an exempt country.”
The Independent has asked the government to correct its online advice and align it with the law.
Note that if you return from the second trip less than 14 days after you originally arrived back from Spain, you must complete the original quarantine. Going abroad again does not absolve the quarantine.
What happens if I break quarantine?
The penalty for failing to comply is £1,000 (reduced to £480 in Scotland).
Who is checking up?
The public health authorities have been making some tracking calls, though the majority of holidaymakers arriving recently from quarantine-obligatory countries appear not to have been contacted.
The resources that will now be required to quarantine will make it challenging for officials to keep tabs on travellers.
The Independent is aware of only one fine being issued for a breach of quarantine, in Lincolnshire
Why has the whole of Spain been included?
Presumably to keep the message simple. The authorities in the four UK nations could have applied the rule for the specific regions of Spain, notably Catalonia and Aragon, where the most significant spikes have occurred.
Instead, they have chosen to enforce the policy for the whole country – including the Balearics and Canary Islands.
This has the possibly unintended consequence of persuading British travellers, who would be at low risk of contracting coronavirus in the Spanish islands, to stay in the UK – increasing the danger to them.
The reason may simply be as banal as the Passenger Locator Form for arriving passengers being designed to deal with whole countries, not parts of them.
What effect will this decision have on the travel industry?
Utter devastation. Just as the travel industry thought 2020 could get no worst, it has. Airlines and holiday companies are already on their knees after the worst four months in their history.
The immediate damage in terms of refunds for cancelled package holidays will run into many tens of millions of pounds.
Airlines that had been hoping to exploit an apparent appetite for Spanish holidays to help fill flights in late July and August now face the prospect of no fresh bookings. They may also have to cancel planned departures because it could be less financially ruinous to pay out refunds than to operate half-empty planes.
The longer-term effects could be even worse.
The weekend when the government chose to make the decision was the busiest so far this summer. Many holidaymakers were setting off on long-planned trips that would provide a welcome escape after months of lockdown.
Instead, many find themselves confused and anxious.
Travel, previously the industry of human happiness, depends on confidence. Now that many dream trips have turned into nightmares, bookings for September and October are now likely to dry up – not just for Spain, but for every other country.
Quarantine is now regarded as the “Martini menace” because the obligation for travellers to self-isolate can evidently be brought in anytime, any place, anywhere.
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