Boris Johnson has announced a dramatic tightening of the UK’s borders, with all international arrivals to be forced to quarantine as well as demonstrate they have had a negative Covid test. After months of criticism of the government’s lax border policies, which Labour claimed were “costing lives”, the prime minister said he was tightening the rules to prevent new variants of the virus reaching the UK and safeguard the vaccination programme. “It is vital to take these extra measures now when day by day, hour by hour, we are making such strides in protecting the population,” Johnson told a Downing Street press conference. Despite some tentative signs that infections may be levelling off, he also underlined the desperate situation facing England’s hospitals, urging the public to think twice before going out at the weekend. “There are now more than 37,000 Covid patients in hospital across the UK and, in spite of all the efforts of our doctors and nurses and our medical staff, we are now seeing cancer treatments sadly postponed, ambulances queueing, and intensive care units spilling over into adjacent wards,” he said. The perilous state of the NHS was underlined by a Guardian analysis that showed two-thirds of all NHS trusts across England were treating more coronavirus patients last week than they did at the peak of the first wave of the pandemic Figures show that in 17 trusts the number of people with coronavirus outnumbered all other patients. On the current trajectory, the number of people being treated for Covid in England’s hospitals could be double that of the April 2020 peak within weeks. With the number of new Covid cases increasing by 55,761 on Friday, and a further 1,280 people reported to have died within 28 days of testing positive, sources made clear the government would await evidence on whether the Covid-19 vaccines prevent transmission before considering laying out a timetable for lifting lockdown restrictions. However, England’s chief medical officer, Prof Chris Whitty, appearing alongside Johnson, said there was early evidence that the measures put in place in London and the south-east had begun to bear fruit in controlling the virus. “The peak of the infections, we hope, already has happened in some parts of the country particularly in the south-east, east of England and London, where there was initially a really big surge with the new variant, and it is fantastic that that is beginning to happen thanks to what everyone has done,” he said. “Other areas that went into lockdown a bit later, that peak will be a bit later.” As well as announcing the new border rules, Johnson hailed the progress of the government’s vaccination programme, saying that almost 3.3 million had received a jab, including 1.3 million people aged over 80 – 45% of the total – and more than 100,000 older care home residents. The new travel restrictions, which will come into force at 4am on Monday, will mean the suspension of all the remaining travel corridors, which had allowed arrivals from certain destinations to avoid quarantine. A new pre-flight testing regime was already due to come into place on Monday morning. It had originally been meant to start on Friday, but was delayed by the government at the last minute after the Department for Transport failed to produce the relevant guidance in time for passengers and airlines to be ready. The government had also already announced that it would halt arrivals from South America and Portugal in an effort to prevent a Brazilian variant of the virus reaching the UK. The additional measures, which also include increasing spot checks on members of the public who should be in quarantine, make it the toughest border policy the government has adopted at any time during the pandemic. Quarantine will last for 10 days, the prime minister said, unless arrivals pay to have a Covid test after five days and receive a negative result. The measures will remain in place at least until 15 February. Johnson faced a grilling this week from the senior Labour backbencher Yvette Cooper, who had urged him to take precautionary measures to prevent new variants of the virus arriving in the UK. Cooper chairs the home affairs select committee, which has repeatedly highlighted shortcomings in the enforcement of travel restrictions since the onset of the pandemic. It is unclear as yet whether the Brazilian variant of the disease that is causing concern, or other new and emerging variants, could be vaccine resistant. Business groups were taken by surprise by the new border measures. Joss Croft, the chief executive of UKinbound, the trade body for the overseas tourism industry, said his members would need financial help from the government. “Consumer safety is paramount and although the removal of all travel corridors is regrettable, given the current trajectory of the virus it’s an understandable decision. With our borders effectively closed, the government needs to provide urgent, tailored support for the inbound tourism industry,” he said. The shadow transport secretary, Jim McMahon, said: “Unfortunately this announcement was inevitable. However, it is closing the door after the horse has bolted.” He added: “The government urgently need to put in place a forward-looking strategy [for] testing on borders and wider controls, while also delivering on the long-promised sector-specific support for those industries who will be so hard hit by this news.”