The UK has updated the list of countries on its green travel list, with upgrades for Malta, Madeira and the Balearic islands, as well as some Caribbean islands.
Israel, which was already green, has now been put on the green watchlist, meaning it is at risk of turning amber.
Eritrea, Haiti, Dominican Republic, Mongolia, Tunisia and Uganda were added to the red list.
The changes cover England and Scotland, with Wales expected to follow.
Northern Ireland made similar changes to its green list but included Kuwait among its list of countries turning red.
The UK government said all measures would be kept under review to protect public health as the top priority.
Transport Secretary Grant Shapps said those red-list countries presented a high public health risk to the UK from known variants, or as a result of very high prevalence of Covid-19.
The changes come into effect from 4am on Wednesday, June 30.
In a boost for travellers wanting to visit amber-list countries, which includes much of Europe, the government announced plans to remove the self-isolation period for amber list countries for those who are fully vaccinated.
Full details will be set out next month, it said.
Currently, there is a mandatory 10-day isolation for passengers from amber countries but it can be done at home.
Mr Shapps said the Government would continue to take a “cautious” approach to reopening foreign travel.
But he said the coronavirus vaccination programme meant it could also start to look at plans for easing restrictions on travel from amber-list countries.
“Thanks to our successful vaccination programme, our intention is that later in the summer UK residents who are fully vaccinated will not have to isolate when travelling from amber-list countries,” Mr Shapps tweeted.
The Department of Transport said: "We expect this to occur in phases, starting with UK residents.
"They will still be required to take a pre-departure test and a test on Day 2, and any positive results will be sequenced to continue to manage the risk of importing variants.
“At the same time, we intend to remove the guidance that people should not travel to amber countries.
"Pending decisions on whether under 18s should routinely be offered vaccination, we will also take clinical advice on whether regular testing can provide a safe alternative to quarantine for children accompanied by vaccinated adults.”
Passengers returning from red-list countries will continue to be separated from other passengers in dedicated terminals to be processed as safely and efficiently as possible, before being transferred to a managed quarantine hotel.
“It is very positive news that ministers are following the science and that fully vaccinated people will be able to travel safely without quarantine later this summer," Heathrow chief executive John Holland-Kaye said.
“We are a cosmopolitan country, a small island with strong links to the rest of the world.
"Exporters want to get out and sell their goods to the world, families want to reconnect after a year of separation.
"We will work with the government to make this happen as soon as possible and let Britain fly.”
Others were less effusive.
ABTA chief executive, Mark Tanzer, said the industry must receive a package of "tailored financial support".
"Every addition to the green list is welcome, but in reality - with several of these popular holiday destinations being placed on the green watchlist - this will not on its own deliver the meaningful restart of international travel that the industry desperately needs," he said.
Johan Lundgren, chief executive of easyJet, said the timetable for reopening was not ambitious enough and that limited reopening was not justified by the data. "The science shows that travel to many European countries would have very little impact on hospitalisations," he said.
Acting general secretary of the pilots' union, Balpa, Brian Strutton, said: “It isn’t good enough to survive on and the absence of any US routes is a bitter blow.“
FULL LIST OF CHANGES
Going green: Anguilla, Antigua and Barbuda, Balearic Islands, Barbados, Bermuda, British Antarctic Territory, British Indian Ocean Territory, British Virgin Islands, Cayman Islands, Dominica, Grenada, Madeira, Malta, Montserrat, Pitcairn Islands and Turks and Caicos Islands will move from amber.
Red light: Dominican Republic, Eritrea, Haiti, Mongolia, Tunisia and Uganda will move from amber to red.
Opening up travel
"The real opportunity we all have now is to open up travel through the double jab," Mr Johnson said.
"If you look at it ... more than 60 per cent of our population now have two jabs, I think 83 per cent have had one jab.
"We’re really getting through it now. The crucial thing is to come forward and get your second jab."
He repeated that travel would be difficult this year after indicating this week that "hassle and delays" would be a feature of overseas trips for a long time.
"I’m not going to claim this summer for travel purposes is going to be like any other summer," Mr Johnson said.
"I don’t want to cast a pall over things but as I said the other day, it will be different."