Boris Johnson has confirmed it will “soon be time” for a quarantine to be imposed on overseas arrivals in the UK.

In his address to the nation on Sunday evening, the prime minister confirmed the widely-expected measure which is designed to stop the spread of Covid-19.

Travel industry leaders have warned the rule would have a “devastating impact” on aviation.

Airlines UK said “ministers are effectively telling people they can no longer travel for the foreseeable future” and called for urgent government support for the aviation sector, which he predicted will ground all remaining operations as a result.

Chief executive Tim Alderslade said: “Public health must of course be the priority and we respect the Sage advice. We all – including government – need to adapt to the new normal but closing off air travel in this way is not the way to achieve this.”

While Johnson did not go into detail of the restrictions, various reports say arrivals into the UK by air will be asked to spend 14 days in self-isolation and will be implemented in early June.

Johnson introduced a Covid-19 alert level in his update that will change the level of lockdown in England.

From Wednesday, people are allowed as much exercise as they like and from this week those who cannot work from home are encouraged to work, but avoid public transport wherever possible.

Shops could begin to open from June, he said, stressing that the return to business would be “phased”.

The hospitality industry could begin to restart from July, he said, adding that any relaxation in social distancing measures would be “conditional” and based on data.

Fines for people breaking social distancing rules are also to be increased, Johnson said.

Rory Boland, editor of consumer group Which? Travel, said: “This news will add to the confusion that British travellers are currently facing when trying to work out whether they can travel as planned, safely rebook postponed holidays, and when they will receive the refunds they are entitled to under consumer law for cancelled trips.”