Covid-19 deaths could be twice as high over the winter as they were in the first wave of the pandemic, PM Boris Johnson is expected to warn MPs later.
In a Commons statement he will say there is “no alternative” as he seeks to win support for a planned four-week lockdown in England from Thursday.
But Mr Johnson will explain he was “right to try every possible option” before ordering people to stay at home.
Labour has said it will back the lockdown but criticised the delay.
Mr Johnson announced at a Downing Street news conference on Saturday that strict measures will include closing pubs, restaurants, gyms, non-essential shops and places of worship.
However, Housing Secretary Robert Jenrick confirmed that moving house will still be allowed during the restrictions, adding that removal firms, estate agents and tradespeople can continue to work but must follow Covid safety guidelines.
Chancellor Rishi Sunak told BBC Radio 4’s Today programme that the UK-wide furlough scheme, which had been due to end on 31 October, was extended until December “to give businesses that ease at this difficult time”.
He said it was his “expectation and hope” that the English lockdown would be “sufficient” to “exit back into the tiered approach” in a month’s time.
Business Secretary Alok Sharma defended the government’s lockdown decision at the Confederation of British Industry Annual Conference on Monday, saying: “The cost of inaction would be greater than the action.”
