What is England's three-tier Covid alert system and which area is in what tier?
The rules will return from December 2 after the country emerges from lockdown, meaning restrictions will be implemented locally rather than nationwide.
Among the changes are the return of some spectator sporting events in a limited capacity in low-risk areas.
Other changes include the closure of restaurants and pubs except for takeaways in the high-risk category, while hospitality venues in medium-risk areas can only serve alcohol with a substantial meal.
The closing time, however, has been extended one hour to 11pm, with last orders called at 10pm.
People will be asked to work from home, where possible, in all tiers.
The allocation of tiers will be dependent on a number of factors, including each area's case numbers, the reproduction rate - or R number - and the current and projected pressure on the National Health Service locally.
Mr Johnson said regions would not be able to negotiate with the government over what tier they are in and the rules will not be tailored to meet specific requests.
He admitted that "many more regions will fall - at least temporarily - into higher tiers than before".
He said: "The scientific advice, I am afraid, is that our tiers need to be made tougher".
Tier allocations will be reviewed every 14 days, and the regional approach will last until March.
Which tier am I in?
Much of the country had baited its breath before the announcement of which areas would be in what tiers.
London and Liverpool avoided the harshest restrictions by being placed in Tier 2 – allowing hospitality venues to open but preventing indoor household gatherings.
But while there was some relief in London and Liverpool, there was misery in Manchester.
The city, which refused to be placed in the toughest tier before lockdown, will now be forced into Tier 3.
Birmingham, Newcastle, Leeds, Hull, Wolverhampton, Blackpool and Kent were also placed in the highest tier.
Only Cornwall, the Isle of Scilly and the Isle of Wight were placed in Tier 1.
What are the rules for Tier 1?
In the medium alert category, people must not socialise indoors or outdoors in groups larger than six.
People are also encouraged to work from home, where possible.
Hospitality venues must close at 11pm, with last orders called at 10pm.
Spectator sport can also return in a limited capacity with crowd restrictions at 50 per cent public capacity of the venue, or 4,000 people indoors and 1,000 people outdoors, which ever is lowest.
Shops, gyms and leisure centres can reopen.
What are the rules for Tier 2?
Under high alert, indoor gatherings between households are banned with the exception of social bubbles for single-adult homes.
People must stick to the rule of six outdoors.
Hospitality venues must only serve alcohol if it comes with a substantial meal, while pubs not operating as restaurants must close altogether.
Attendance at spectator sport is reduced to 50 per cent capacity, or either 2,000 people outdoors or 1,000 people indoors, which ever is lowest.
People who live in Tier 2 areas must continue following Tier 2 rules when they travel to a Tier 1 area.
Shops, gyms and leisure centres remain open.
What are the rules for Tier 3?
People who live in areas of very high alert must not meet with anybody who is not in their household.
Hospitality venues including restaurants and pubs must close if not operating a takeaway or delivery service.
Accommodation such as hotels, B&Bs, campsites, and guest houses must close except for business travellers and those who use these venues as their prime residence.
Indoor entertainment and tourist venues must close.
Spectator sport and other events must not take place.
People are also told to avoid travelling to other parts of the UK.