British Prime Minister Boris Johnson faces a large rebellion among his Conservative lawmakers on Tuesday in a parliamentary vote over new restrictions to try to curb the spread of the new Omicron coronavirus variant.

British Prime Minister Boris Johnson

The measures, including ordering people to work from home, to wear masks in public places and use COVID-19 passes to enter some venues, are expected to be approved by parliament but with Johnson relying on the opposition Labour Party for votes.

It's yet another blow to a prime minister already under pressure over reported parties in his Downing Street office last year when such gatherings were banned, a pricey refurbishment of his apartment and the chaotic withdrawal from Afghanistan.

Many of his lawmakers say the restrictions are draconian, with several angry over the introduction of vaccination certification, dubbed COVID passports, to enter some venues, such as night clubs.

"It is quite wrong that people should be expected to produce what is essentially a health ID card before they can access services that should be available to all," said Conservative lawmaker and former minister, David Jones.

"People should certainly be encouraged to have the vaccine ... but ultimately people have to take responsibility for their own health. To deny unvaccinated people access to services is to create a two-tier society. That is not the sort of country most of us would want to live in," he told Reuters.

Lawmakers are due to start consecutive votes on the measures in turn from 1830 GMT.

The government says the measures are necessary to stem the spread of Omicron, which accounts for more than 40% of infections in London and is expected to become the dominant strain in the British capital.

One person has died after contracting the variant and 10 people have been hospitalised with Omicron across England.

The government is moving to try to win over the Conservative rebels, saying that people who have not been double-jabbed can instead offer proof of a negative lateral flow test to gain access to indoor venues of more than 500 people.

"On the issue of certification ... it requires proof of a negative test unless you are double vaccinated and it allows us to keep some of these settings open which is vital for hospitality," the spokesman said on Monday.