Travellers should expect longer waiting times at UK borders as the Government switches to a traffic light system for international travel.

Border Force director Paul Lincoln said passengers must accept there will be increased delays at “each stage” of their journey, with staff required to check “100%” of all travellers coming through.

His comments came as Transport Secretary Grant Shapps announced that 12 countries – including Portugal, Gibraltar and Israel – would be added to the Government’s green list for travel.

From May 17, people in England will be able to visit those destinations without having to enter quarantine on their return.

But Mr Lincoln told a Downing Street press conference on Friday that the introduction of health checks at the border meant it now takes, on average, five to 10 minutes for staff to process each passenger arriving into the UK.

He said: “For the time being, passengers will need to accept an increase in the time taken at each stage of their journey.

“It currently takes a Border Force officer five to 10 minutes to complete all the necessary checks, which means that even for the most compliant passenger, it might take 14 or 15 times longer to process than before, compared to around 25 seconds.

“Where people do not have the correct paperwork, it can and has taken considerably longer, including when we need to serve fixed penalty notices for non-compliance.”

Mr Lincoln said Border Force was still under instruction from ministers to check “100% of passengers” but that it would be making some paperwork digital, such as the passenger locator form, in a bid to “speed up” the process, while more staff would be made available to carry out checks.

Heathrow Airport’s chief executive said the Government must “urgently address the unacceptable situation” at the UK border.

John Holland-Kaye said in a statement: “Long immigration queues are an inevitable result of under-resourcing, not an inevitable result of extra checks.”