The UK's compulsory 14-day quarantine for inbound travelers, by air, rail or ferries, came into force on the country's borders from Monday amid protests from the airline industry.
As part of a phase by phase easing of the coronavirus lockdown within the country, all passengers - except a small number of exemptions for essential workers - will have to fill out an online locator form giving their contact and travel details and the address of where they will self-isolate for two weeks.
Regulations for England include fixed penalty notices of GBP 1,000 (USD 1,268) or prosecution for anyone who breaches the rules, with police being allowed to use "reasonable force" to make sure people comply.
British Airways has begun legal proceedings after sending a pre-action letter to ministers on Friday. Backed by Ryanair and EasyJet, it released a joint statement to urge the government to rethink the measures.
"These measures are disproportionate and unfair on British citizens as well as international visitors arriving in the UK," the statement reads.
"We urge the UK govt to remove this ineffective visitor quarantine which will have a devastating effect on UK's tourism industry and will destroy (even more) thousands of jobs in this unprecedented crisis," it said.
UK Border Force officers will carry out checks at the border and may refuse entry to a non-resident foreign national who refuses to comply with the regulations. However, officers have expressed concerns that they have not had enough time to familiarise themselves with the new requirements.
UK Home Secretary Priti Patel has insisted the 14-day quarantine rule is "backed by the science" and is "essential" to save lives.
"We know they will present difficulties for the tourism industry, but that's why we have an unprecedented package of support, the most comprehensive in the world, for both employees and businesses," the Indian-origin Cabinet minister said.
"But we will all suffer if we get this wrong. That's why it's crucial that we introduce these measures now," she said.
She had tabled the rules in the House of Commons last week and set a June 28 date for the first review of the measures.
The British government is considering international travel corridors, or so-called air bridges, to allow future quarantine-free travel from destinations deemed safe in terms of the level of coronavirus infections, which has claimed over 40,000 lives in the UK.
Meanwhile, Britain remains in the early stages of lockdown easing, with the guidance for people to continue to avoid non-essential travel. The next stage of a further lifting of restrictions, including for retail and other shops under COVID-secure conditions, is expected from next Monday.
