MPs will vote later on the plan for a four-week lockdown in England.
The restrictions, which include the closure of pubs, restaurants gyms and non-essential shops, will come into force after midnight if approved.
It comes as the head of NHS England warned there are 11,000 coronavirus patients in hospital in England - up from 2,000 at the start of October.
Sir Simon Stevens also said the NHS would be "geared up" to deliver a potential vaccine before Christmas.
Meanwhile, Prime Minister Boris Johnson has told business leaders the lockdown, which is due to end on 2 December, will not be extended beyond that date.
'Very substantial increase'
Speaking to BBC Radio 4's Today programme earlier, Sir Simon said there had been a "very substantial" increase in "desperately sick patients in hospitals" in October.
He said: "So, put another way, we've got 22 hospitals' worth of coronavirus patients across England.
"And indeed, even since Saturday, when the prime minister gave his press conference, we filled another two hospitals full of severely ill coronavirus patients."
A number of Conservative MPs have criticised the nationwide lockdown.
But Labour's support for the new measures mean they are highly likely to be approved, even if there is a rebellion from Tory backbenchers.
Sir Simon said the actions taken by Parliament would mean the health service should be able to avoid postponing routine operations.
He also said the NHS would be writing to GP practices this week to get them prepared to deliver a vaccine by Christmas, if one becomes available.
Sir Simon said: "There are over 200 vaccines in development and we believe that we should hopefully get one or more of those available from the first part of next year.
"In anticipation of that, we're also gearing the NHS up to be ready to make a start on administering Covid vaccines before Christmas, if they become available."
Sir Simon later told a briefing the NHS's "central expectation" was that a vaccine would be possible by the start of next year.
He said: "The bulk of this is likely to be the other side of Christmas, but we want to be ready in the event that those optimistic signs you've been hearing about come to pass. "
And he suggested that all patient-facing NHS staff would soon be given routine testing, regardless of symptoms.
Meanwhile, Mr Johnson apologised to businesses for the "nightmare" Covid situation.
In a pre-recorded speech to the Confederation of British Industry's annual conference, the prime minister said the restrictions went "against every free market instinct I possess".
"And, believe me, we will end these autumn measures on 2 December when they expire," he added.
Ahead of the expected new restrictions, a number of retailers and other businesses are extending their opening hours to meet a surge in demand.
From Thursday, non-essential retailers and other businesses including hairdressers will be required to close until the lockdown is lifted.
Couples have rearranged weddings ahead of the lockdown, which prevents them taking place for all except those who are seriously ill and not expected to recover.
Guidance for 'clinically vulnerable'
And updated guidance has been published for those deemed to be extremely vulnerable, including advice that people should not attend work if they cannot do it from home.
The extremely vulnerable group has been expanded to also include adults with Down's Syndrome.
The advice also says that most children originally on the shielded patient list no longer need to be because of the very low risk of them becoming sick from coronavirus, and can therefore attend school.
Labour first called for a short lockdown or "circuit-breaker" in England last month and have criticised the government for not acting quickly or decisively enough.
BBC political correspondent Iain Watson said that Labour's support will be enough to deter some Tories who have criticised the measures from rebelling, because they would see it as a "senseless sacrifice".
"A relatively small number, however, will still vote against their own government," our correspondent said.
The BBC has been told that former chief whip Mark Harper, who has openly criticised NHS Test and Trace, is expected to be among them.
A very senior Tory privately described the handling of the pandemic as a farce.
Others have been pushing for an economic assessment of the lockdown to be published, and several MPs questioned the data informing the government's decisions.
On Tuesday, Prof Chris Whitty, England's chief medical officer, defended lockdowns, telling MPs they were the only practical option to stem the spread of Covid-19 until a vaccine and better drugs become available.
Among the Conservative MPs to criticise the nationwide lockdown during a parliamentary debate on Tuesday was Richard Drax, who said they were "destructive, divisive, and don't work".
"They simply delay the inevitable - the re-emergence of the virus when lockdown ends, as has been shown," he said.
"Have we over-reacted? Yes, I think we have. A draconian, onerous and invasive set of rules and regulations now govern our very existence."
Meanwhile, Commons Health Committee chairman Jeremy Hunt said it would be "quite unforgivable" if the UK this winter saw similar levels of Covid transmission in hospitals as experienced during the first coronavirus wave.
Speaking to Today, he called for more routine testing of NHS staff to be carried out.
More details of England's lockdown have also been revealed this week, with the publication of the legislation that will bring them into force.
The regulations specify fines starting at £100 for rule breakers, potentially rising to a maximum of £6,400 for repeat offences.
Chief constables of five north-west England police constabularies have signed a letter committing to greater levels of enforcement of Covid-19 coronavirus restrictions during the lockdown.
The published regulations also reveal:
- There will be an exemption allowing veterans to participate in Remembrance Sunday and Armistice Day events
- People will also be allowed to visit friends or "close family members" in prison
- Visits to friends or "close family members" who are near to death will also be allowed
- There will be a 10pm curfew on restaurants to make takeaway deliveries
The new rules replace a tiered system of different local restrictions across England, which ministers say they want to return to after the country-wide lockdown is due to end on 2 December.
The UK recorded a further 397 coronavirus deaths and 20,018 confirmed cases on Tuesday.
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