Summer holiday plans for nearly six million Britons could be ruined if Spain and Greece follow France onto the “amber plus” list requiring isolation on return, according to analysis.

A new category within the traffic light travel system implemented for British holidaymakers has effectively been created.

Alongside Red, Amber, and Green, Amber Plus is a new level that travellers should become familiar with.

The new Amber Plus category comes after it was announced that all travellers, regardless of vaccination status, returning from France to England from 19 July will need to continue to follow previous quarantine rules despite the new changes made to those returning from Amber countries.

This is what you need to know.

What is the traffic light system?

The traffic light system refers to how countries around the world are rated for Covid-19, and the rules regarding each country will vary depending where they lie in the scheme.

Destinations are assigned a colour, either Green, Green watchlist, Amber or Red, based on a range of Covid-19 measures, such as vaccination numbers, infection rates and the presence of virus variants.

The different colours indicate the risk of travelling to each location.

The Government states that you “should not travel to red list countries or territories”.

What are the rules for those returning from France?

The Government announced: “From Monday 19 July, UK residents arriving from amber countries who are fully vaccinated will no longer have to quarantine, although they will still need to comply with necessary testing requirements.”

However, it was revealed that the change would not apply to France, “following the persistent presence of cases in France of the Beta variant, which was first identified in South Africa”.

Anyone returning to England who has been in France in the last 10 days will be required to quarantine on arrival in their own accommodation, and will need to arrange day two and day eight Covid-19 tests, regardless of their vaccination status.

“This includes any fully vaccinated individual who transits through France from either a Green or another Amber country to reach England,” a statement from the Government explains.

The Amber Plus category lies between the Amber list and Red list - it requires the quarantine time of the Red list without the need for travellers to go through the process at a hotel.

According to The Guardian, ministers are discussing whther to add mainland Spain and the Balearic Islands to the list alongside France.  

What has been said about the rule change?

Health Secretary Sajid Javid said: “We have always been clear that we will not hesitate to take rapid action at our borders to stop the spread of COVID-19 and protect the gains made by our successful vaccination programme.

“With restrictions lifting on Monday across the country, we will do everything we can to ensure international travel is conducted as safely as possible, and protect our borders from the threat of variants.”

Transport Secretary Grant Shapps added: “Travel will be different this year and whilst we are committed to continuing to open up international travel safely, our absolute priority is to protect public health here in the UK.

“We urge everyone thinking about going abroad this summer to check their terms and conditions as well as the travel restrictions abroad before they go.”

Will other countries be added to the list?

As it stands, it is only France that is included on the Amber Plus list, however it is likely that we could see more countries added.

Data expert Tim White took to Twitter to discuss the move when it was announced.

In a long thread of Tweets, he wrote: “Let’s start by recapping what we know about #France #Greece and #Spain and their variants.

“So #France was nonsensically put on Amber+ for <4% of Beta cases from a very small sample. It really does seem the govt advisors could not read the data, but unlikely to admit a mistake.

“So if that level is the new benchmark, then there is a problem for #Spain and #Greece. But Spain does so little genomic sequencing it’s going to be as outrageous as the France decision if it is made Amber+ too.”

He wrote that “either all of Spain and islands go Amber+, or none”, and that “Belgium, Netherlands and Germany must be at risk too, low incidence of variants in previous data”.

However, according to a source at The Times, “Spain is unlikely to go to Amber Plus”.

How long will Amber Plus be its own list?

According to the i, the Government is expected to do away with the controversial category in the next review, shifting France to the Amber list.

Speaking to LBC, Environment Secretary George Eustice said: “There was a reason at the time that the advice was we should put France on that amber (plus) list, it was concern about the Beta variant and the fact that the vaccine might be slightly less effective against that.

“But as those rates come down obviously the evidence will change and it can be reviewed and we will want to be putting countries like France back onto the amber list in the normal way.”

It would mean that destinations such as Greece and Spain would remain on the Amber list, following concerns that they could end up on the Amber Plus list.

A Department for Transport spokesman said: “The travel list allocations have not changed for Spain or Greece.

“We are closely monitoring the data and will take swift action on travel list allocations and international travel requirements should the data show that countries’ risk to England has changed.”

The devolved administrations in Scotland, Wales and Northern Ireland set their own rules in terms of the requirements for arrivals from overseas, but their rules are often closely linked to the position in England.