Boris Johnson has warned summer travel will be filled with “hassle and delays” as he played down the prospect of freedoms for the vaccinated.

The Prime Minister said Britons faced a “difficult year for travel” regardless of whether he presses ahead with plans to scrap travel quarantine rules for double-jabbed Britons.

Ministers on the Cabinet’s Covid-O committee are expected to meet on Thursday to consider the vaccination travel plans and whether to expand the quarantine-free green list.

On Tuesday, more than 400 of the world’s biggest travel and tourism companies will publish an open letter to Mr Johnson, warning that Britain faces losing £639 million a day in July if he fails to reopen foreign travel by lifting restrictions on vaccinated holidaymakers. 

An analysis also showed the green list could be expanded to another 14 countries including US, Balearics, Italy, Croatia and Barbados if the UK used the same health risk criteria as the EU which is already opening up foreign travel. 

On a visit to a laboratory in Hertfordshire, Mr Johnson said the Government would “certainly be looking” at exempting vaccinated holidaymakers from quarantine but added: “I want to stress that this is going to be, whatever happens, a difficult year for travel. 

“There will be hassle, there will be delays because the priority has got to be to keep the country safe and stop the virus coming back in.”

He poured cold water on the prospect of easing the remaining coronavirus rules early, on July 5, refused to rule out future lockdowns and warned the nation should brace for a “rough winter”.

He said delta variant cases, hospitalisations and admissions to intensive care are still rising and the country must be “cautious” as new official data showed the mutant strain is now dominant in more than 300 local authority areas in England.

Covid variants — Traffic light list

Mr Johnson said it was “looking good” for domestic Covid restrictions to be lifted at the “terminus point” of July 19 as he said the “vaccination rollout is going gangbusters”.

But he declined to rule out reimposing tougher curbs later in the year as he warned “some new horror” could emerge which “we simply haven’t budgeted for”.

Government sources played down any significant reopening of foreign travel before August and indicated that countries were more likely to be added to the red list than turn green this week. 

“We are not going to get to the point for a long time of it being easy to travel again and everyone being on holiday. It is going to be a gradual process,” said one source. “There is still going to have to be checking of people at the borders and other people who are not vaccinated.”

Under the plan to revise quarantine restrictions, the 10-day isolation period could be replaced by daily lateral flow tests but it is unclear when this could be introduced. Matt Hancock, the Health Secretary, said: “We’re not ready to be able to take that step yet, but it’s something that I want to see and we will introduce, subject to clinical advice, as soon as it’s reasonable to do so.”

In their letter to the Prime Minister, the World Travel and Tourism Council (WTTC), which represents 400 major firms including Tui, Marriott, Hilton and cruise lines urged him to ditch quarantine for vaccinated travellers from amber countries from June 28, when the traffic light system is reviewed.

Travel countries on the red, green and amber list

It follows new NHS Test and Trace data revealing that none of the 23,000 travellers returning from amber countries carried variants and only one in 250 (0.4 per cent) tested positive for Covid.

If Britain adopted the EU green list criteria of infection rates below 75 cases per 100,000 of the population and positivity test rate below four per cent, it would add the USA, Croatia, Canada, Italy, Germany, Balearic Islands, Mexico, Jamaica, Finland, Poland, Morocco, Malta, Barbados, Grenada, according to analysis by The PC Agency. 

But with few – if any – countries expected to be added to the green list this week, Paul Charles, the Agency’s chief executive, warned that the UK is likely to fall further behind the EU which is already opening up not only internally but also to the US. He noted Lufthansa had brought in 747 passenger jets to fly German holidaymakers out of Frankfurt to the beaches and bars of Mallorca.