Business trips and family Christmas holidays were left in disarray after all travellers arriving in the UK were told they must self-isolate for two days until they have a negative Covid PCR test.

Boris Johnson said the “tough” restrictions were needed to “buy time” for the country after the emergence of the new omicron variant.

The news was met with dismay by the travel industry, who described the move as a “huge blow” to a sector that was only just “getting back on its feet”.

The new rules, which are expected to come into effect within days, mean travellers will again have to fork out for the more expensive Covid tests that can cost anywhere from £25 to £400 per person. Short business trips to the UK could be hit hardest with the requirement to isolate on arrival.

Under the new rules, travellers from any destination will have to take a PCR test before the second day after their arrival and will only be able to stop isolating after they get a negative result.

The new rules will apply to travellers whether they have had both vaccine shots or none.

Business leaders warned that the new measures would “effectively kill” short business trips.

‘Tough measures for everybody’

Richard Lee, a business manager, said: “This seems massively disproportionate. Why not use a PCR entry test like most other countries? Having to isolate will effectively kill short high-value business trips again.”

Another, Bobby Lane, the CEO of the business services company Factotum, said: “This has big implications for people that have booked holiday or business trips and can’t get the extra time off of work or change their plans at this late stage.”

At a press conference on Saturday, Mr Johnson said the new travel restrictions were needed to “buy time” so UK scientists could figure out how dangerous and vaccine resistant the new strain is.

He said: “What we are announcing are some tough measures for everybody travelling so that you have to do a PCR test as soon as you get back here and you have to isolate for 48 hours until you get a negative result.

“I am afraid that may sound tough but that is just the way it has got to be.”

The move marks a sharp reversal from ministers, who had been easing Covid travel restrictions until the emergence of omicron.

From the summer, ministers have allowed travellers with both vaccine shots to take the cheaper lateral flow tests when they return from abroad.

Last month, the Government also wound down the highest tier of travel restrictions – red list countries – which saw people returning having to quarantine in a state-approved hotel for 10 days.

However, the red list was brought back on Thursday after the new variant was confirmed in South Africa. The country and five surrounding African nations had direct flights suspended and people returning back from those countries were told they had to isolate at home for 10 days.