What’s happening from Monday?
All international arrivals into the UK, including returning British residents, will be required to self-isolate for 14 days.
They will be required to fill in a contact locator form with contact and travel information so they can be reached if they, or someone they may have been in contact with, develops coronavirus.
The exemptions list includes road haulage workers, a registered health or care professional travelling to the UK to provide essential healthcare and Eurotunnel drivers.
What can and can’t I do while under quarantine?
The rules mirror those established for people self-isolating with coronavirus symptoms.
Individuals quarantining will be permitted to shop for food essentials and medicines but only if it is not possible to rely on others, and will be able to take public transport to their designated accommodation.
A breach of self-isolation would be punishable with a £1,000 fixed penalty notice in England or potential prosecution and unlimited fine. The devolved administrations in Scotland, Wales and Northern Ireland will set out their own enforcement approaches.
About a fifth of people are expected to receive a spot-check to ensure that they are staying at the address or addresses they have provided to the authorities, the Guardian understands.
Why is the UK bringing in quarantine rules now?
Amid the worldwide pandemic, arrivals at UK airports have fallen by 99% compared with a year ago, arrivals by sea are 97% lower and international rail arrivals are down by 98%.
But the government says it is the right time to introduce the rules because the number of new arrivals is expected to rise as lockdowns are eased, at the same time as the rate of domestic Covid-19 infection in the UK is falling.
However, the timing is contentious. Some have questioned the logic of blanket quarantine measures at a time when most European countries are in a much improved position than that of the UK.
Why is it causing a political row?
Dozens of cross-party MPs have raised concerns about the potentially limited impact on public health amid warnings of the severe damage that could be caused to the travel and aviation industry.
More than 200 travel and hospitality companies have called on the government to change planned quarantine rules, which they say will be unworkable and deeply damaging to their industry.
Are there alternatives to quarantine?
There have been calls from the travel industry and politicians for “air bridges” to be introduced, allowing quarantine-free travel to and from countries with low Covid-19 infection rates.
However, this proposal overlooks one significant requirement: the reciprocal agreement of the destination country.
At a time when the UK has some of the worst infection rates in Europe, it is unlikely that all countries will be willing to welcome UK residents or allow their own citizens to travel to and return from the UK.
Earlier this week, Denmark eased its border restrictions to allow travel to Norway and Germany but not to its neighbour Sweden due to the latter’s controversial approach to tackling Covid-19.
A few countries, such as France, have indicated they would be willing to do a deal with Britain that could allow some travel to continue.
What have other countries done?
Many countries in Europe are requiring a similar period of quarantine to the UK’s.
However, the big difference in the UK’s approach is not now but what it did earlier on in the pandemic.
Prof Gabriel Scally, president of epidemiology and public health at the Royal Society of Medicine, previously described the UK as an outlier in its approach to the border with more than 130 countries introducing more stringent restrictions when the coronavirus outbreak began. These included screening, quarantine and bans on travel from high-risk areas.
Conversely, as the UK is set to introduce its most restrictive measures at the border to date, many countries are now looking at ways to slowly ease restrictions that have been in place since March.