France shut its UK border for 48 hours on Sunday amid fears of a new coronavirus variant. More than 50 countries have now banned UK arrivals.
Home Secretary Priti Patel said 650 lorries are stacked up on the M20, with a further 873 at a lorry park.
The UK's top scientist has warned the new variant is "everywhere".
Sir Patrick Vallance added that further restrictions are likely to be needed in more areas of England.
In England, 17 million people are under tier four rules, the toughest level, where people are being told to stay at home and not leave the area. Some parts of England, as well as Wales, have asked people who travel from tier four areas to self-isolate.
US-based Samuel Chu of Hong Kong Democracy Council says he ‘would be overjoyed to welcome them as they seek asylum’ in the country.