Requiring travellers arriving in the UK to go into quarantine will cost millions of tourism jobs, Ryanair boss Michael O’Leary has warned.

He said his airline is experiencing a “collapse of inward bookings” for flights this summer, because people are being told to self-isolate for 14 days under Government measures to guard against a second wave of coronavirus.

All passengers, bar a handful of exemptions, now have to fill out an online locator form giving their contact and travel details, as well as the address of where they will isolate.

Mr O’Leary told Good Morning Britain: “We’re seeing thousands of British families booking their holidays in Portugal, in Spain and Italy, but there’s almost a collapse of inward bookings bringing those Italians, bringing those Europeans here to the UK, on which Britain’s tourism industry depends, particularly in the peak months of July and August.

“What’s irrational about it is all of those countries have a much lower Covid rate than the UK.”

He added: “Millions of jobs are going to be lost in British tourism because British hotels, British guest houses, British visitor attractions – all over London, the Globe, the London Eye, Madame Tussauds – will be empty, because the hundreds of thousands of Italians and Spanish and French people you get coming to Britain every July and August simply won’t travel.”

Ryanair joined rival airlines easyJet and British Airways in starting legal proceedings over the “disproportionate and unfair” policy.

Airline Jet2 said it would delay the resumption of its flights and holiday programme from July 1 to July 15 “in view of the ongoing travel restrictions that are in place as a result of the Covid-19 pandemic”.

It added: “Customers who were due to travel before July 15 do not need to contact us. We are continuing to proactively contact customers to discuss their options, one of which is rebooking their holiday to a later date.”

It comes as Health Secretary Matt Hancock told the Downing Street press briefing the virus was in retreat and suggested people should not give up entirely on the idea of a holiday – particularly in the UK.

Mr Hancock said: “For those who aren’t able to go abroad for a holiday, I know the impact that that will have this summer. I understand that.

“I just hope that we will be able to get to a position where people will be able to go on holiday – including domestically – safely, carefully and in a Covid-secure way.”

The Health Secretary said because coronavirus is “in retreat”, the Government could proceed with further plans to ease the lockdown, such as the opening of non-essential shops from June 15.

He said the figures on deaths, recorded positive tests and an almost 50% fall in the number of new care home outbreaks were “good news”.

Mr Hancock added: “When you look across the board, it is clear that coronavirus is in retreat across the country.

“But we must be vigilant and we must be cautious, and we are taking a safety first approach.

“It means that we can proceed with our plan of making some changes, for instance looking towards the proposals that have been made next week on the retail sector, and that people can have confidence to take their children to school in the three years that we’ve opened so far.”

Earlier, Mark Tanzer, chief executive of travel trade organisation Abta, called on ministers to outline a “coordinated plan” for encouraging people to travel to and from the UK.

He said: “We must restart international travel as soon as it is safe to do so, and businesses and customers would benefit from the Government outlining when this is likely to happen.”

People who fail to comply with the new rules could be fined £1,000 in England, and police will be allowed to use “reasonable force” to make sure they follow the rules.

Border Force officers will carry out checks on arrivals and may refuse entry to a non-resident foreign national who refuses to comply with the regulations.

Failure to complete the locator form will be punishable by a £100 fixed penalty notice.

Lucy Moreton, professional officer at the Immigration Services Union, said Border Force staff checking quarantine papers were “angry” at the way they were being treated.

She told BBC Radio 4’s Today programme that technical papers explaining to staff what to check for only arrived on Friday, and were still not available to those operating on the front line of the devolved administrations.

Ms Moreton added: “This does appear to be very shambolic and they don’t want to be blamed for that.”

The quarantine regulations must be reviewed every three weeks, with the first taking place by June 29.

They could be in place for a year, when the legislation expires, unless the Government decides to scrap them sooner.

Travellers arriving from within the Common Travel Area, which includes Ireland, the Isle of Man and the Channel Islands, will not need to self-isolate unless they have arrived in the CTA in the last 14 days.

Home Secretary Priti Patel said: “The science is clear that if we limit the risk of new cases being brought in from abroad, we can help stop a devastating second wave.

“That is why the measures coming into force today are necessary. They will help control the virus, protect the NHS and save lives.”

The policy came into force as:

– Human trials of a potential vaccine for Covid-19 developed by a team from Imperial College London will begin in the UK next week.

– The Department of Health and Social Care said another 77 people had died after testing positive for coronavirus in the UK as of 5pm on Saturday, the lowest daily total since March 23, though figures are regularly lower at weekends.

– The global death toll passed 400,000, according to data collected by Johns Hopkins University.