The move comes just one week after thousands of football fans travelled from England to Portugal to watch the Champions League final.
Portugal is now classed as an amber list country with UK tourists no longer permitted to travel to the sunny destination with limited exceptions.
According to the BBC, the decision was made following discussions between UK and devolved governments and advice from the joint biosecurity centre.
Here is everything you need to know about the change.
What is the travel advice to Portugal?
From Tuesday travel to Portugal from the UK for leisure will not be permitted, according to reports.
After Tuesday travellers returning to the UK from Portugal will be required to take a COVID-19 test, book and pay for day 2 and day 8 COVID-19 travel tests – to be taken after arrival in England and quarantine at home or in the place they are staying for 10 days
How does the traffic light system work?
They determine the quarantine and coronavirus testing requirements people will face when returning to England once the ban on overseas leisure travel is lifted.
Travellers returning from a country on the green list will not need to quarantine, and will only be required to take one post-arrival test.
But travelling to many of the destinations on that list won’t be quite so easy, with entry to Australia, New Zealand, Singapore, Brunei, and the Faroe Islands severely restricted.
The amber list covers popular holiday destinations such as Spain, France, Italy and Greece, and people returning from amber countries must take two post-arrival tests; Transport Secretary Grant Shapps has said “you should not be travelling to these places right now”.
Everywhere else is currently on the red list; those returning from a red list country must stay in a quarantine hotel for 11 nights at a cost of £1,750.
Could guidance change?
The lists can be amended at any time, but wholesale changes are not expected to occur until the situation is reviewed at “checkpoints”.
The list will be reviewed every three weeks, with The Telegraph reporting the second batch of ‘green list’ countries could be published in the week leading up to 7 June.
A third updated list is likely to be revealed in time for a review of the government’s foreign travel policy on 28 June.
Will I need a 'vaccine passport’?
Once travel restrictions have lifted, people travelling will be asked to prove their Covid-19 vaccination or negative test status before being allowed to fly, and will be able to prove their status in either paper or digital form.
Digital certification will be available on the NHS app from Monday 17 May, which is free to download and was originally designed to allow people to book appointments and access other health services.
Anyone without a smartphone is being asked to avoid calling their GP and instead ring 119 to order a letter confirming their vaccination status.
What’s the current Covid-19 situation in Portugal?
Portugal has a slightly higher case rate than the UK.
The UK recorded 4,430 on June 2, compared to 724 in Portugal. While the UK recorded more cases, Portugal’s population is far lower at 10.17 million people compared to 66.8 million.
At 20% the percentage of Portugal’s population fully vaccinated is also far lower than the UK (50%).
For the latest information and travel advice for Portugal and beyond, head to the Foreign, Commonwealth and Development Office’s (FCDO) website
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