Greece has been left off the UK's quarantine-free country travel list.
The government is expected to announce a full list of countries under a traffic light system which will decide which nations are safe to travel to today.
Under the traffic light system Britons holidaying in “green” or “amber” countries will not have to self-isolate for 14 days when they get back.
But people returning from countries in the 'red' zone would need to self-isolate.

The list is set to include 60+ countries but the Transport Secretary Grant Shapps confirmed this morning that quarantine rules will not be lifted next week for travellers arriving from Greece.
Mr Shapps told BBC Radio 4’s Today programme: “Greece won’t be on the list in the first place because Greece have said that on July 15 that’s their next review of their own systems.
“Reciprocity can’t come before July 15 for Greece and that is a matter for Greece themselves.”.
The Greek government had previously said it would resume flights between the two countries on June 15.
But officials later reversed this decision and delayed the reopening until July 1.
But Greece then extended its ban on flights from the UK until July 15 despite reopening its borders to international visitors on Wednesday this week.
The policy was agreed at a meeting of government officials chaired by prime minister Kyriakos Mitsotakis.

He reportedly said: "The whole opening procedure is dynamic and the data will be continuously evaluated."
Flights from Sweden are also included in the extended ban.
Tui, the UK's biggest tour operator, was due to serve four Greek islands when it resumes its operations for UK customers on July 11.
They along with Jet2, British Airways, easyJet and Ryanair were forced to cancel flights for thousands of customers.
And Brits may be banned from holidaying in several other countries due to the Leicester lockdown, according to reports.
The Times claims some countries have raised alarm over the safety of opening to UK holidaymakers because of the Leicester lockdown.
Cyprus may be one of those countries to ban Brits from going on holiday due to the rise in coronavirus infections in Leicester, officials have warned.
Cyprus is putting countries into categories based on their coronavirus risk levels with those in category C banned from entering.
The UK is understood to be in this category with Dr Petros Karayiannis telling the Cyprus Mail that we may face a wait to be promoted to category B which requires passengers to test negative for coronavirus to be able to enter the country.
He said: "This depends on the epidemiological picture it will present in the coming days”.
Noting the lockdown in Leicester, the professor of Microbiology/Molecular Virology at the University of Nicosia Medical School, said: "If there is a wide spread, then it will be difficult to integrate the UK even into category B."