England will begin a month-long lockdown on Thursday - with Boris Johnson saying acting now could allow families to spend Christmas together.
Pubs, restaurants, gyms, non-essential shops and places of worship will close, but schools, colleges and universities can stay open.
The announcement has sparked anger from some Tory MPs, and business leaders have warned of a "bleak midwinter".
Mr Johnson is expected to deliver a statement in the Commons on Monday.
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MPs will vote on the latest restrictions on Wednesday, and Labour has indicated it will back the lockdown.
But writing in the Sunday Telegraph, former Conservative leader Sir Iain Duncan Smith accused the prime minister of "giving in to the scientific advisers".
Sir Iain said the Scientific Advisory Group for Emergencies (Sage) had "pressurised" the government into taking this decision, with its members "publicly lecturing" the government.
He urged Mr Johnson not to continue "encouraging businesses to reopen only to force them to lock down again".
Under the new restrictions:
People will be told to stay at home except for specific reasons
These include work which cannot be done from home, childcare or education, exercise outdoors, medical reasons, essential shopping, providing care for vulnerable people or for volunteering, and visiting members of your support bubble
Meeting indoors or in private gardens will not be allowed, but individuals can meet one other person from another household outside in a public place
Non-essential retail will close, but can remain open for click-and-collect delivery
Pubs, bars, restaurants will have to close, but can still provide takeaway and delivery, excluding takeaway of alcohol
Indoor and outdoor leisure facilities, such as gyms and swimming pools, will also close, along with entertainment venues and personal care facilities such as beauty salons
Places of worship will close, unless they are being used for funerals, to broadcast acts of worship, individual prayer, formal childcare, or essential services such as blood donation or food banks
Construction sites and manufacturing workplaces can remain open
Weddings and civil partnership ceremonies will not be able to take place except in exceptional circumstances, and funerals will be limited to a maximum of 30 people
Children will still be able to move between homes if their parents are separated
Clinically vulnerable people will be asked to be "especially careful" but people will not be asked to resume shielding
Overnight stays, staying in a second home, and holidays will not be allowed - including in the UK and abroad - although there are exceptions, such as work trips
People will be told to avoid all non-essential travel by private or public transport
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Hours before the furlough scheme was due to end, the government said that it would be extended until December, covering 80% of employee wages.
Dame Carolyn Fairbairn, Confederation of British Industry director general, said extending furlough was a "vital step", adding that affordable mass testing would be the "game-changer" for businesses, enabling more companies to stay open.
She said: "For many businesses, a second national lockdown marks the start of a bleak midwinter."
Both the chief executive of the British Retail Consortium, Helen Dickinson, and the chief executive of the New West End Company, Jace Tyrrell, described the lockdown as a "nightmare before Christmas".
Meanwhile, travel firms have warned of a "complete shutdown" across the industry when England goes into lockdown again and have called for the government to support the sector.
England's Catholic Church strongly criticised the government for banning communal worship in the new lockdown, saying such gatherings have been a great help to the nation's wellbeing.
The president and vice-president of the Catholic Church's Bishops' Conference - Cardinal Vincent Nichols and Archbishop Malcolm McMahon - said the latest restrictions would bring "hardship, distress and suffering" and called on the government to explain its reasons for the ban.