London mayor Sadiq Khan has said the introduction of Tier 4 restrictions was “devastating”

“This 11th-hour announcement is a bitter blow for families who were looking forward to spending time with their families, to businesses who had planned for a decent few days, particularly in the retail sector because of the awful year they’ve had,” he told the BBC.

“It’s the chop-change, stop-start, that’s led to so much anguish, despair, sadness and disappointment and I’m afraid it makes it really difficult for people like me to ask people to listen to us when we keep on changing our minds.”

Asked about scenes at London’s railway stations on Saturday night, where hundreds of people sought to leave the capital before the tier rules were tightened, Mr Khan said: “What you saw yesterday was a direct consequence of the chaotic way the announcement was made.

“I understand why people want to return to see their mums, dads, elderly relations, but I think it’s wrong.

“Let me tell you why I think it’s a mistake either going yesterday or thinking about going today. Yesterday, technically speaking, you may not have been breaking the rules but you may well have the virus and not realise you have got the virus.

“You may be taking that virus with you from London to your mum, dad, elderly relations.”

Health secretary Matt Hancock has said the number of people being vaccinated is “accelerating and rising fast”.

As of 8pm on Saturday, around 350,000 people in the UK had received a first jab of the Pfizer/BioNTech vaccine, according to Mr Hancock, who added that the government is aiming to increase this number to roughly 500,000 by the end of the weekend.

A total of 400 different sites have been set up across the country now, the health secretary said.

He refused to be drawn on when the Oxford vaccine – of which the UK has 4 million doses ready to go – will be approved by the drugs regulator.

Dr Chaand Nagpaul, British Medical Association (BMA) council chair, has said the planned five-day Christmas relaxation initially outlined by the government did not follow the science.

When asked on Sky’s Sophy Ridge On Sunday how concerned he was about the new strain of coronavirus, Dr Nagpaul said: “We were concerned at the time the Prime Minister announced the five-day relaxation for Christmas because the science told us then that the virus was spreading week-on-week.

“It just did not follow the science to relax the rules.

“Last Wednesday, before the new variant was announced, it was obvious that the infection was spreading at a dangerous level, the NHS was in a dangerous state, and again, the science wasn’t followed when in fact we should have reversed the Christmas relaxation rules.

“So whilst there is a new variant, we didn’t need the new variant to reverse this rule and the public could of course have been given greater notice, but there’s no doubt it was the right and necessary decision.”

Sophy Ridge of Sky News has just asked health secretary Matt Hancock how the government knows the new variant isn’t more deadly.

Mr Hancock insists that the government’s scientists have thoroughly examined the new strain and assessed 1,000 cases that have so far been associated with the mutated version.

These teams have been able to examine the disease that followed these infections, along with previous cases that have been retrospectively identified by the UK’s surveillance network, and the government is “confident” that the new strain isn’t more potent, says Mr Hancock.

Adam Wagner, a human rights barrister, outlines the legislation behind the new lockdown regulations in the handy Twitter thread below. The main takeaway? Tier 4 is essentially lockdown 3.0. But as severe and harsh as the new restrictions may seem, the scientists have insisted they are wholly appropriate.

“Regardless of this new virus variant, from a purely virological/epidemiological viewpoint, the new restrictions over Christmas and the new Tier 4 for the hardest hit London/Southeast areas are a necessary measure to control this virus,” says Dr Julian Tang, a virologist at the University of Leicester.

Sydney was isolated from the rest of Australia on Sunday after all of the country’s states and territories imposed travel restrictions on its residents as a coronavirus cluster in the city grew to around 70.

All flights between UK airports and the Netherlands have been grounded until the new year.

In the early hours of Sunday morning, the Dutch health ministry issued a statement saying the decision was based on the discovery of the “infectious mutation of the Covid-19 virus” that is circulating in Britain.

 The Dutch government says the flight ban will initially apply until 1 January 2021.

Simon Calder, our travel correspondent, has more on this story:

Good morning and welcome to our live global coverage of the coronavirus pandemic. I’ll be bringing you the latest news as it happens from the southeast of England in tier 4.