Ministers face more pressure over the planned blanket quarantine for travellers to the UK after an expert questioned the Government’s claim that the scheme was “backed by science”.

Controversy over the plan continued as Boris Johnson prepared to urge world leaders to “unite humanity in the fight against disease” as he hosts an online global vaccine summit on Thursday aiming to raise £6 billion to immunise millions of children in the world’s poorest nations.

The summit comes after the Prime Minister braced the nation for more bad news on the economy, saying at Wednesday’s Downing Street briefing: “I am afraid tragically there will be many, many job losses. That is just inevitable.”

But in the wake of that warning, the travel industry pressed home its message that the quarantine plan risked worsening the economic pain by hampering attempts to get people moving again and taking holidays.

Ryanair boss Michael O’Leary said the plans would “do untold damage to British tourism.

“We don’t understand, as an industry, why the British Government doesn’t follow the European science that says it is perfectly OK to fly as long as you all wear face masks.”

And he alluded to a report in the Times that the PM’s chief aide was behind the plan, telling the BBC it was “designed by Dominic Cummings for Dominic Cummings, who as we all know, doesn’t observe quarantine”.

He spoke as Professor Robert Dingwall, a scientific adviser to the Government and member of a sub-group of Sage (Scientific Advisory Group for Emergencies), said there was no evidence of new clusters of Covid-19 infection involving people who have been travelling abroad.

“I think we would really need to get the level in this country significantly further down before quarantine started to become a useful measure.

“That I think, even then, we would have to see something that is targeted on countries with a significantly higher level of community transmission than ourselves – and there aren’t too many of those around, I’m afraid.”

Northern Ireland Secretary Brandon Lewis defended the quarantine policy, insisting it was “the right time to do it”.

But he admitted under the new rules a family from Spain could visit the Lake District for a holiday, while a family from London cannot.

He told BBC Breakfast: “As long as they are following the guidance and doing the quarantine as outlined, and giving the details to Public Health England (PHE), somebody from abroad can come to the UK but they will have to quarantine for 14 days.”

The plan, under which people arriving in the UK from overseas will have to undergo a 14-day quarantine period from Monday, will be kept under review and alternatives such as international travel corridors between countries were being worked on, Mr Lewis said.

In other developments:

– Mr Lewis told the BBC that ministers were “absolutely determined” to “publish very clear statistics” on its test and trace programme, having only
declared that “thousands” of people have been contacted, once the UK Statistics Authority is satisfied with the proposals.

– the Bank of England was preparing to publish a list of companies which receive funding through its Covid Corporate Financing Facility lending scheme.

– the Society of Motor Manufacturers and Traders (SMMT) said demand for new cars fell by 89% last month as the coronavirus lockdown hit sales

– around 1,500 jobs faced the axe along with 12 showrooms at struggling car dealership Lookers as the group announced plans to slash costs

– Aston Martin has said it plans to cut up to 500 jobs as part of a major restructuring.

Meanwhile, MPs heard industry warnings on Thursday that tens of thousands of aerospace and aviation workers are set to lose their jobs as a result of the crisis.

Industry expert Paul Everitt, chief executive of the ADS Group, said redundancies will be made in the coming weeks and months because of the collapse in demand for flights.

He told the Business, Energy and Industrial Strategy Committee it was “very difficult” to see demand return quickly, so airlines and other companies will be forced to restructure or “resize”.

And Stephen Phipson, chief executive of Make UK, told MPs that one in four manufacturers were planning to make redundancies in the next few months.