Eight boroughs have now gone above the key threshold of 100 new cases a week per 100,000 population.
Four more are just below this level which is seen as one of a series of potential trigger points for stricter measures.
Any new restrictions are likely to be city-wide and the infection rate for the capital as a whole has risen to close to 90 cases per 100,000 people.
Ealing has the highest Covid-19 rate in London at 136.9 cases per 100,000 in the week to October 9, with 468 cases, according to an analysis by the Evening Standard.
Richmond has a rate of 133.3 (264 cases), Hackney and the City of London area 124.8 (363 cases with the vast majority of them in Hackney) , Redbridge 124.5 (380 cases), Harrow 114.7 (288 cases), Haringey 109.4 (294), Barnet 106.3 (421), and Hammersmith & Fulham 101 (187).
What would it mean if London moves up to Tier 2?
Under Tier 2 restrictions Londoners would 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.
What will Tier 3 restrictions involve?
Social mixing will be banned both indoors and in private gardens, while pubs and bars will be told to close unless they can operate as a restaurant.
Local leaders will help to determine whether other venues should be closed, such as gyms or casinos, in very high alert level areas.
People will also be advised against travel in and out of the areas.
In areas where premises could only remain open as restaurants, officials said the expectation was that drinks could only be served with a substantial meal – a bag of crisps would not suffice.
The proposed legislation uses the term “table meal”, saying alcohol can only be sold as part of one which “might be expected to be served as the main midday or main evening meal”.
Which areas are in Tier 1?
London and the rest of England, apart from the places listed in Tier 2 and Tier 3.
Which areas are in Tier 2?
Cheshire West and Chester
High Peak – the wards of Tintwistle, Padfield, Dinting, St John’s, Old Glossop, Whitfield, Simmondley, Gamesley, Howard Town, Hadfield South and Hadfield North
Blackburn with Darwen
Redcar and Cleveland
Oadby and Wigston
Which areas are in Tier 3?
The Liverpool City Region.
This includes the local authority districts of Halton, Knowsley, Sefton, St Helens and Wirral, as well as the City of Liverpool.
Indoor gyms and fitness studios will close from Wednesday, as well as sports facilities, leisure centres, betting shops, adult gaming centres and casinos, while wedding receptions will not be permitted, according to Downing Street.
Will schools or shops be shut at any level?
No. Schools, non-essential retail and universities will remain open in all levels, according to Downing Street.
How do I find out exactly which tier my home is in? Is there a postcode checker?
Yes. There is a search feature on the Government’s website enabling people to check which restrictions apply to each local area.
Users simply need to enter their postcode into the field provided. It can be accessed here.
What happens next?
Measures are to be kept under review, and the secretary of state will review Tier 2 areas at least once a fortnight, and restrictions under Tier 2 once every 28 days.
There will be a four-week sunset clause for areas facing the toughest restrictions.