The Guardian claims to have been told such a scheme could come into effect in August and would be based on several factors, including progress of vaccine certificate agreements.

According to The Guardian, the system was discussed in early March as part of plans to restart international travel.

International travel is not expected to restart until 17 May "at the earliest" according to prime minister Boris Johnson’s Covid roadmap, and is yet subject to a report by the Global Travel Taskforce due on 12 April.

The Cabinet Office, meanwhile, is carrying out a review of domestic vaccine certification which could unlock various aspects of the leisure and hospitality industries.

This review, the Department for Transport has said, will be "closely integrated" with the Global Travel Taskforce’s work.

Johnson’s spokesperson would not be drawn on the possibility of linking a vaccination certification scheme with a traffic light system when questioned on Monday, The Guardian reports.

The EU Commission announced plans last week for a digital green pass regime, which would allow travellers to verify their Covid status through a vaccine certificate or negative test for travel.

The Guardian said travel to countries designated "green" would be based on vaccine pass agreements.

The Telegraph, meanwhile, carried a similar report on Monday, suggesting the UK government’s current hotel quarantine "red list" would remain in place, albeit subject to change, while travel to and from countries designated "amber" would depend on pre-departure testing and self-isolation.

Jersey has announced it will reintroduce its traffic light system from 26 April. There, those arriving from the UK and other Crown dependencies from 26 April will have to provide their travel history in advance via an online portal, and submit to PCR testing for Covid-19 on days five and 10 following their arrival.

Green zone arrivals will have to isolate until they have a negative result from their arrival test; those arriving from amber zones will have to self-isolate until they receive a day five negative test result, and those from red zones a day ten negative test result.

The reports in both The Guardian and The Telegraph followed a string of comments from ministers and scientists feeding into the government’s Scientific Advisory Group for Emergencies (Sage) over the weekend suggesting international travel would pose a significant risk of the UK importing new Covid-19 variants that could be resistant to the vaccines currently being rolled out.

Several leading travel industry figures said the speculation was unhelpful, and called again on the Global Travel Taskforce to come up with a robust framework that would allow travel to resume in a more seamless manner than via last summer’s travel corridor system.

Julia Lo Bue-Said, chief executive of the Advantage Travel Partnership, said: "The speculation over the weekend with regards to summer holidays not being possible this summer is damaging to the travel industry and consumer confidence, and serves no purpose until we see what is announced in the Global Travel Taskforce report.

"As we’ve already seen throughout the pandemic, a lot can happen in the space of a few months. While a ’traffic-light system’ may work in terms of highlighting which countries are safe to travel to, what we don’t want is countries coming on and off the list like last year.

"This causes confusion for travellers, dents consumer confidence for those who have booked trips and throws up huge operational challenges for travel agents and the travel industry."

‘Tiered, risk-based system’

Tim Alderslade, chief executive of Airlines UK, the trade body representing UK-registered airlines, said its focus was to work with ministers on a framework for travel "that is robust and workable, and can stand the test of time as we enter the all-important summer period".

"We know universal, restriction-free travel is unlikely from 17 May but under a tiered system, based on risk, international travel can meaningfully restart and build up, with minimal restrictions in time."

Which? Travel editor Rory Boland added the government should make safety, affordable tests, vaccine certification and clarity about refunds when travel is disrupted top priorities.

"So far as it is possible, rules and requirements for travel should remain consistent, as confusion and changes will leave travellers footing the bill again and further risk undermining consumers’ confidence in booking travel," said Boland.