The Prime Minister is expected to outline urgent action to force arrivals to the UK to quarantine in hotels for 10 days. The measures are similar to those already in place in countries such as Australia.
With Covid mutations being found across the world, scientists fear a vaccine-resistant variant could accidentally be imported to Britain.
The jabs are already thought to be less efficient against a mutant strain of the virus found in South Africa.
Last night Ministers and scientists met to discuss what further measures could be taken to reduce the risk of new strains of the virus arriving in Britain.
It is thought the plans to be unveiled will not apply to all nations and instead be limited to those returning from 30 countries already covered by the travel ban, including those in South America, Portugal and Cape Verde, as well as South Africa and neighbouring nations.
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Passengers will be expected to cover the price of the hotel themselves, with costs set to be as high as £1,5000 per person for the 10 day quarantine.
The UK has already given 6.8 million people a first dose of a coronavirus jab and is on course to have the entire adult population vaccinated by September.
Meanwhile, the number of coronavirus infections in the UK is continuing to decrease.
Yesterday there were 20,089 new coronavirus cases recorded, a drop of two-thirds compared to three weeks ago.
The import of a vaccine-resistant variant of the virus would be a major set back in the UK’s path back to normal.
In accordance with parliamentary convention, Home Secretary will inform MPs of the plans in the House of Commons this afternoon ahead of Mr Johnson’s briefing to the nation.
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The Prime Minister will host the Downing Street press conference at 5pm tonight.
It will be the third televised briefing in three days after Mr Johnson also addressed the nation last night to apologise after the UK virus death toll surpassed 100,000.
He said he was “deeply sorry” for the loss of lives and said he took “full responsibility for everything that the Government has done”.
Mr Johnson pledged to honour those who had died at the hands of coronavirus and those working in hospitals to fight the pandemic in a national day of commemoration.
He said: “I offer my deepest condolences to everyone who has lost a loved one: fathers and mothers; brothers and sisters; sons and daughters and the many grandparents who have been taken.
“And, to all those who grieve, we make this pledge: that when we have come through this crisis, we will come together as a nation to remember everyone we lost, and to honour the selfless heroism of all those on the front line who gave their lives to save others.
“We will remember the courage of countless working people – not just our amazing NHS and care workers, but shop workers, transport staff, pharmacists, teachers, police, armed forces emergency services and many others – who kept our country going during our biggest crisis since the Second World War.
“We will commemorate the small acts of kindness, the spirit of volunteering and the daily sacrifice of millions who placed their lives on hold time and again as we fought each new wave of the virus, buying time for our brilliant scientists to come to our aid.”