Video report by ITV News Political Editor Robert Peston
A new three-tier system to 'simplify' local Covid restrictions for England has been announced by Boris Johnson in a bid to curb rising coronavirus cases and deaths.
But what restrictions will be implemented within the 'medium', 'high', or 'very high' Covid alert levels?
And which area has been placed under the strictest coronavirus measures?
What is happening?
Different parts of England will be split up into 'medium', 'high' or 'very high' local Covid alert levels under the new system Boris Johnson has announced.
The new restrictions comes just a day after the prime minister held a telephone conference with Cabinet colleagues to discuss the situation and ongoing negotiations with local leaders in the north of England.
Non-essential retail, schools and universities will remain open in all alert levels.
What is the Covid three-tier system and what does it all mean?
The three tiers represent an advancing scale of local restrictions.
What is the Medium Covid alert level?
Under the first tier - medium - restrictions will be the baselines ones which are in place across all areas of England which are not under tougher local restrictions.
These measures include the "rule of six" - a ban on most gatherings of more than six people and a 10pm curfew for pubs, bars and restaurants.
What is the high Covid alert level?
Under tier two - high - restrictions are the same as tier one, but with the added ban on indoor mixing of households or support bubbles is not allowed.
This is similar to the rules currently in place in Middlesbrough and parts of the North East.
However, two households may be allowed to meet outdoors in a private garden, as long as the rule of six and social distancing guidelines are followed.
Nottinghamshire, East and West Cheshire and a small area of High Peak will move into the 'high' alert level, along with most other local lockdown areas.
There is advice for people to minimise their journeys if they live in an area of 'high' alert.
The PM said the 'high' alert level primarily aims to reduce household to household transmission, by preventing all mixing between different households or support bubbles indoors.
What is the very high Covid alert level?
Under tier three - very high - measures include the closure of pubs and bars, betting shops, casinos, and gyms.
However, restaurants and pubs serving food will be allowed to open, so long as customers remain seated and different households cannot meet up and mix.
Cross-household socialising will be banned in all settings, including private gardens, except outdoor public places such as parks, where the rule of six will apply.
The prime minister confirmed that these restrictions are expected to last for four weeks at a time, before being reviewed.
On Monday, Boris Johnson announced the Liverpool City Region will be under the new Covid very high alert measures from Wednesday.
How is it decided which area goes in to which tier?
Mr Johnson said infection rates will be used to determine what alert level an area is placed under, but Downing Street said the final decision will be a human one rather than it being triggered by a threshold being passed.
A postcode checker will be launched on the government's website to advise people what guidance applies to their area.
What support is available for businesses which have to close?
At a Downing Street briefing on Monday, Chancellor Rishi Sunak said councils in local lockdown areas will get around £500 million extra to help with enforcement and other logistics.
He also announced an extra £1.3 billion of funding for Scottish, Welsh and Northern Ireland administrations “if they choose to do something similar”.
The chancellor also stressed that the existing furlough scheme will continue in October and the Job Support Scheme will be available from November and will run for six months.
On Friday, Mr Sunak expanded the Job Support Scheme, revealing that the government will pay two-thirds of wages for workers who are legally unable to attend their jobs due to lockdown restrictions.
He also said that businesses legally required to close in England will be able to claim cash grants of up to £3,000 per month and the money does not need to be repaid.How have Labour responded?
Sir Keir Starmer said he is "sceptical" whether the government has a plan to get control of the virus.
He added that it increasingly feels as if Boris Johnson is "several steps behind the curve".
The Labour leader said: "I have to say to the prime minister, I am now deeply sceptical that the government has actually got a plan to get control of this virus, to protect jobs or retain public trust."