Crowds of Londoners who fled the British capital on Saturday night hours before tighter Covid-19 restrictions were introduced were called "totally irresponsible" for ignoring expert advice to stay at home.
Images emerged of busy train stations after Prime Minister Boris Johnson scrapped a plan to allow up to three households to meet over five days during the Christmas period, after a surge in cases in south-east England and the emergence of a new strain of the virus that spreads more easily.
Many services from London train stations were fully booked hours after Mr Johnson's announcement.
"This was clearly totally irresponsible behaviour, the chief medical officer was absolutely clear that people should unpack their bags if they had them packed," said Matt Hancock, the UK's Health Minister.
“I think it is relatively small numbers and the large, vast majority of people throughout this whole pandemic have followed the rules, been responsible and played their part and I want to thank everybody for doing that.
“It is more important than ever that people are responsible, not only stick to the rules, but even within the rules restrict social contact as much as is possible because this is deadly serious,” he told Sky News.
A new top tier of pandemic restrictions was announced, with more than 16 million people in London and some surrounding areas now under "stay at home" orders that mirror the national lockdown earlier this year.
People in Tier 4 are being told to act as though they have the virus, while non-essential shops and businesses are being closed.
Even in lower tier areas in England, Scotland and Wales, the relaxation of rules over the festive period is now applicable only on Christmas Day.
Mr Johnson was accused of "gross negligence" by Keir Starmer, the leader of the UK's main opposition party Labour, for failing to take action soon enough.
“I think the Prime Minister should apologise,” he said. “This is not just one mistake when he has otherwise got things right. It is the same mistake over and over again.
“At the heart of the problem here is a Prime Minister who simply doesn’t want to be unpopular and therefore won’t take the tough decisions that are necessary, until he is forced into them at the 11th hour. We can’t go on like that.”
Mr Hancock said a new national lockdown was not inevitable but that the new virus strain "will be very difficult" to keep under control until enough people are vaccinated.