European countries have banned flights and ferries carrying passengers from the UK in a desperate attempt to suppress the spread of a new variant of the coronavirus that has plunged south-east England into a tier 4 lockdown. In the most dramatic development, France announced it was suspending passenger and human-handled freight transport from the UK for 48 hours from 11pm GMT. The Road Haulage Association warned the move would have a “devastating effect” on supply chains already disrupted by Brexit stockpiling and pandemic restrictions. The UK government said it expected “significant disruption in Kent” as a result of the French move and was “urging everybody – including all hauliers” to avoid travelling to ports in the county until further notice. The travel bans came as the latest figures showed the new variant of Covid-19 is causing an alarming rise in infections, particularly in London and south-east England, with UK cases rising by 35,928 on Sunday morning – the fourth time in a week that the daily figure has exceeded 30,000. As countries including Germany, Italy, Ireland and the Netherlands introduced bans on arrivals from the UK, British ministers admitted the latest lockdown measures – imposed just days before Christmas and with the immediate shutting down of high street stores in the busiest week of the year – may have to remain in place for months. Amid deepening criticism of Boris Johnson’s handling of the pandemic, senior Conservative MPs have reacted angrily to the timing of the lockdown, with some accusing the prime minister of deliberately delaying a decision to place millions of people in London and the south-east under new measures to avoid parliamentary scrutiny. Johnson’s announcement on Saturday evening has been seized upon by Labour as evidence of “gross negligence”, accusing him of offering false hope to millions that they could enjoy a family Christmas. The new strain of the disease was first detected in September. The government has been aware of it since October, but resisted pleas from scientists and doctors for further lockdown measures. Some 21 million people in England and Wales affected by the new restrictions are being told to stay at home, with the planned relaxation of rules for Christmas now cancelled, while non-essential shops and businesses must close. For the rest of England, Scotland and Wales, relaxed indoor mixing rules over the holidays have been cut from five days to Christmas Day only. On Sunday, the health secretary, Matt Hancock, said the additional restrictions for southern England might have to remain for “the next couple of months” while a vaccine was rolled out. “The cases in the tier 4 areas have absolutely rocketed in the last few days … We have got a long way to go to solve this,” he told Sky News’ Sophy Ridge on Sunday. Johnson will chair an emergency Cobra meeting on Monday to discuss “the steady flow of freight into and out of the UK” as well as international travel restrictions, a Downing Street spokesperson said. No 10 added: “We are working closely with Kent Resilience Forum, Kent council and Highways England to ensure contingency measures are urgently put in place to manage disruption.” France said it would use its 48-hour suspension of travel from the UK to agree on a new testing regime in collaboration with its EU partners. Long queues of passengers formed inside St Pancras station on Sunday afternoon as they attempted to catch the Eurostar to Paris. Eurotunnel said access to its Folkestone terminal would be suspended for passenger and freight traffic from 11pm, while the Port of Dover said it was closing to all lorry traffic and asked “accompanied freight and passenger customers not to travel to the port”. Rod McKenzie, policy director at the Road Haulage Association, said: “The French ban will have a devastating effect on the supply chain. “We have seen in recent days the queues on both sides of the channel because of Brexit stockpiling and the Christmas rush and now border closures will mean everything including perishable food supplies will be impacted.” Dublin is to impose a 48-hour ban on travel from Britain, Ireland’s transport minister confirmed, while Germany was suspending flights from midnight on Sunday. The Netherlands was the first country to announce a travel ban, to remain in place until at least 1 January. Belgium also said it was suspending flight and train arrivals from Britain from midnight for 24 hours. Austria, Bulgaria, the Czech Republic, Italy, Sweden, Romania, Iran, Saudi Arabia, Turkey, El Salvador and Kuwait also announced travel bans. Sir Charles Walker, vice-chairman of the influential Tory backbench 1922 Committee, said he believed that ministers had known before Friday they would be cancelling Christmas. “I suspect the government knew they were going to cancel Christmas on Wednesday and Thursday when they were still telling the House of Commons they planned to press ahead,” he told BBC Radio 4’s The World This Weekend. A No 10 spokesperson dismissed that claim. “The prime minister was informed of the high transmission rate of the new variant of the virus and its rapid spread in the south-east on Friday afternoon. We had to take rapid action to contain the disease and slow the spread,” she said. Another Tory backbencher told the Guardian that MPs using a WhatsApp group were “seething” at the prime minister’s last-minute decision, which has left thousands of people’s plans in chaos. “This is a failure of leadership for which we may never be forgiven. Many people were blaming previous cock-ups on Dominic Cummings. Now, it is all on the PM,” the MP said. The Labour leader, Sir Keir Starmer, criticised Johnson’s lack of decisive action over the new strain. “It was blatantly obvious last week that the prime minister’s plan for a free-for-all over Christmas was a risk too far. “And yet, rather than listening to concerns and taking them seriously the prime minister did what he always does. Dismissed the challenge, ruffled his hair and made a flippant comment,” he told a press conference on Sunday. “It is an act of gross negligence by a prime minister who once again has been caught behind the curve,” he added. At a No 10 news conference on Saturday, Johnson said he was taking the actions with a “heavy heart”, but the scientific evidence had left him with no choice. Johnson’s announcement came as a hammer blow to many businesses hoping to pick up some pre-Christmas sales and prompted a rush to London train stations. Footage posted on social media showed large crowds at St Pancras station waiting to board trains to Leeds. Johnson’s announcement was followed by further restrictions in Scotland and Wales. Wales went into tier 4 from midnight on Saturday. Rules had been due to be relaxed to allow people to celebrate Christmas from 23 to 28 December, but instead the relaxation will now only be allowed on Christmas Day. Nicola Sturgeon announced a travel ban into Scotland from the rest of the UK, and said the toughest level of coronavirus restrictions would apply across the country for three weeks from Boxing Day. Four of the five power-sharing parties in Northern Ireland are calling for an emergency meeting of the executive to discuss the new strain of Covid-19 found in England. Sunday’s concerning developments came down to the prevalence of the newly identified VUI2020/12/01 strain of the virus. The government’s New and Emerging Respiratory Virus Threats Advisory Group (Nervtag) presented evidence that it was spreading far faster than other versions, and that the existing tier 3 restrictions could not drive down its spread. Dr Yvonne Doyle, medical director at Public Health England, said: “This sharp and sudden increase is of serious concern.” Most of the new cases were concentrated in London and the south-east – where the new strain is thought to have originated – although it was too soon to say if they were linked to it. Additional reporting by Daniel Boffey