One public health expert has said the capital needs to enter Tier 3 “within 48 hours” or risk a “terrible situation” and rising deaths over Christmas.
Officials fear it is now too late to turn the tide before the capital is locked into tighter restrictions, despite the Tier review not being scheduled to take place until December 16.
Professor John Ashton, a former regional director of public health for north-west England, said: “[The government] needs to decide in the next 48 hours whether to move London into tier 3 otherwise they really risk a terrible situation for London, with deaths going up during the Christmas period.”
He also warned: “They might have to go to complete lockdown.”
The city was placed into Tier 2 when England exited its national lockdown a fortnight ago – but rates of infection have been climbing since before then.
Health Secretary Matt Hancock spoke of “worrying signs” in London yesterday.
The city has now overtaken the north-east and north-west where most regions are subject to tier three rules.
In the north-west, which had seen the most infections in the UK for a long time, the rate is down to 130 per 100,000 – but London is now at 177 cases per 100,000 people.
Cases could continue rising as Londoners flock to bars and shops now restrictions have eased.
Mayor of London Sadiq Khan added: “The number of cases in London are rising again and if we don’t all work together now we may face tougher restrictions across the capital.
“Londoners have worked incredibly hard to help bring down the number of cases before, but we must not risk undoing all the sacrifices that have been made by lowering our guard and allowing cases to rise further ahead of Christmas.”
A spokesman for Mr Khan said people in the capital must follow the rules or risk being placed into a Tier 3 lockdown.
“If we begin to act like this virus has gone away we could see a devastating further surge in cases at a time of year when our NHS is already under enough pressure,” the spokesman said.
“The number-one way to look out for our loved ones and support local businesses in this festive season is to follow the rules and do all we can to avoid going back into tougher restrictions, later this month or any time in the future.”
Nickie Aiken, Conservative MP for the Cities of London and Westminster, told The Standard: “We want and need London to stay in Tier 2 rather than Tier 3.
“Every Londoner has got a role to play in that by keeping to the rules.”
The PM has promised some Tier 3 areas with lower rates or a trend of declining cases that they could drop down a tier in next week’s review.
Any tier changes would come into effect on December 19.
But London’s Mayor Sadiq Khan said plunging the city into the most extreme tier would be “catastrophic” to businesses already struggling under the Covid pandemic.
The Times reports sources said Tier 3 was “more than likely” if the cases continue to shoot up.
Pessimistic Whitehall sources said even if cases levelled off, there was “almost certainly” no way Tier 3 could be avoided.
But London MPs are expected to push back against the measures hard with cases varying widely from borough to borough.
Insiders are calling for low-infection suburbs to be exempt from the restrictions.