London will be moved into Tier 2 coronavirus restrictions from midnight on Friday, with millions of people living in the capital banned from mixing between households indoors, in restaurants and pubs .
London was initially placed in the medium Tier 1 category.
Here, we explain what Londoners can expect from the new measures.
What are Tier 2 restrictions for London?
London was originally placed under Tier 1 restrictions, meaning it was considered to be at a "medium" risk.
This meant no new restrictions were immediately imposed, with the rule of six and the 10pm curfew remaining in place.
However under Tier 2 Londoners face:
A ban on mixing between households in homes although support bubbles would still be permitted,
The rule of six would continue to apply in gardens and other outdoor settings.
Pubs and restaurants would remain open but the ban on mixing between households indoors would apply to the hospitality sector, which would be a devastating blow to the industry.
When will the new restrictions come into force?
MPs were told on Thursday that London will be moved to Tier 2 coronavirus restrictions from midnight on Friday.
Business Minister Nadhim Zahawi had earlier signalled earlier that London would be moved into tighter Tier 2 Covid-19 restrictions as early as Friday.
Meanwhile Mr Khan warned the capital could be moved upwards “very quickly – potentially even this week”.
In a letter to the Prime Minister, the Mayor of London said as the rate of infections in London was “fast approaching” 100 cases per 100,000, it was “likely” the capital would move to the next alert level as early as this week.
In another interview, he said that London will pass the "trigger point" to enter Tier 2 restrictions in the next few days.
A spokesman for Mr Khan said on Wednesday: “The virus is now spreading very quickly in every corner of London.
“The number of cases is rapidly increasing and all the indicators we look at are moving in the wrong direction.
“As of today, London is at ‘medium’ in the Government’s new alert levels. However, Londoners should understand that this could change very quickly – potentially even this week.”
How many cases are there in the capital?
A swathe of west London, as well as several council areas in east London, have seen the disease rise above this level.
Ealing has the highest rate in the capital at 144.8 per 100,000 in the week to October 10, with 495 cases, up from 87.2 and 298 cases for the previous seven days, according to an analysis by the PA news agency.
Richmond is second with a rate of 137.9 (273 cases), with 100.5 (199 cases) the previous week, Hackney and City of London 128.2 (373), 100.7 (293) the previous week, with the vast majority of the cases in Hackney rather than the Square Mile, Redbridge 123.5 (377), 107.5 (328) the previous week, Harrow 119.0 (299), 89.2 (224), Haringey 117.3 (315), 85.2 (229), Hammersmith and Fulham 115.6 (214), 71.3 (132), Barnet 111.9 (443), 80.8 (320), Hounslow 111.2 (302), 73.7 (200), Hillingdon 102.6 (315), 72.3 (222), and Newham 101.9 (360), 72.2 (255).