New rules requiring all people arriving in the UK to self-isolate for 14 days have come into effect.

Those arriving by plane, ferry or train - including UK nationals - must give an address where they will self-isolate. Rule breakers will be fined.

Home Secretary Priti Patel has said the laws were designed "to prevent a second wave" of coronavirus.

But the boss of Ryanair has said the rules are a "political stunt" and are not a quarantine.

Michael O'Leary told the BBC: "You could be in Sainsbury's, you could be on the beach, you could be on the golf course in the unlikely event the Home Office calls you - all they will have is a mobile number."

He claimed even the Home Office acknowledged the rules were unenforceable.

Some industries have warned they will be severely impacted by the rules, and Mr O'Leary warned of devastation.

Despite criticism from businesses, Ms Patel has said the measures are "proportionate" and being implemented "at the right time".

What are the new rules?

For more on the rules click here.

Almost all travellers have to fill in a "public health passenger locator" form on arrival. Failure to do so could lead to a penalty of £100, or travellers may be refused entry.

If they are unable to provide an address, the government will arrange accommodation at the traveller's expense. It says there will also be checks to see whether the rules are being followed.

'Complex' rules

Anyone arriving from the Republic of Ireland, the Channel Islands or the Isle of Man does not have to complete a form or enter quarantine.

There are also exemptions for workers in some industries such as road haulage and medical professionals who are providing essential care.

The union representing UK Border Force staff said the rules were complex and they were not fully prepared.

Lucy Moreton, professional officer at the Immigration Services Union, told the BBC that technical papers explaining what to check for only arrived on Friday and were still not available to those operating on the front line. She said there 42 categories that were exempt from the quarantine rules.

Ms Moreton added there was no system for checking addresses and only flagrant rule-flouters - such as using the name Mickey Mouse - would be picked up.

An internal memo, seen by the BBC, told Border Force agents that the fines would not apply to passengers arriving in the UK through Ireland, who are covered by a separate set of rules.

The travel industry has been vocal in its criticism of the government's quarantine rules, warning that the isolation period will deter visitors and put jobs at risk.

The manufacturing industry has also highlighted that fewer flights will restrict imports and exports, which will have a knock-on effect for the freight industry, as well as hampering the recovery of some businesses.

British Airways, EasyJet and Ryanair have written to Procurator General Sir Jonathan Jones, the government's most senior legal official - the first stage required when taking legal action against the government.

The airlines say they are prepared to ask for a judicial review into the government's travel quarantine rules.

Travel trade body Abta has called on the government to urgently create a roadmap for restarting international travel, while the UK's biggest airport services company, Swissport, has warned it could deliver a "killer blow" to the tourism sector.

Industry leaders wrote to Prime Minister Boris Johnson in May asking that the government avoid taking a "blanket approach" to quarantine, suggesting so-called "air bridges" with countries that have low coronavirus rates.

Aviation, maritime and rail industry leaders were invited to discuss the new quarantine plans but British Airways refused to attend the meeting, and aviation bosses told the BBC that they were not impressed by the content of the call.

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BA is proposing to make 12,000 staff redundant. Separately, Heathrow Airport's chief executive has warned that about 25,000 jobs could be at risk at Heathrow Airport.

Government sources have told the BBC that the UK is hoping to secure air bridge agreements with certain countries, such as Portugal, Spain and France, as well as Australia and Singapore.

But the government's position is that the idea is only "under consideration".

In other developments:

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