A booster jab will be needed as a requirement to qualify as fully vaccinated, the health secretary has said.
Sajid Javid told MPs on Monday that, once all Brits have had a fair opportunity of getting a booster jab, the government wants them to become necessary to obtain a pass indicating "full vaccination" status.
"Subject to this House, you'll need to show a negative lateral flow test to get into nightclubs or large events with an exemption for the double vaccinated," said the health secretary.
"Once all adults have had a reasonable chance to get their booster jab, we intend to change this exemption to require a booster dose."
The strain has shown an ability to evade immunity induced from two jabs – however, a third dose of a vaccine helps provide adequate protection.
According to early data, those vaccinated with just two doses saw immunity drop significantly for Omicron, but those that received a booster of Pfizer enjoyed 70% level of protection against symptomatic infection.
The move to a third vaccination being a requirement for proof of full vaccination would bring the UK in line with countries like Israel, where a third jab has been a requirement for months.
The health secretary's words come ahead of a controversial vote in the House of Commons on vaccine passports in response to the emergence of the new Omicron variant of Covid.
Vaccine passports for large venues are part of the government's "Plan B" measures, which also includes working from home guidance and mandatory mask wearing in settings like public transport and shops.
However, Boris Johnson is facing significant rebellion by Conservative MPs in the House of Commons on Tuesday over the measures, with over 70 already expressing their intention to vote against the government's proposals.
Senior Tory MP and lockdown sceptic Steve Baker said he was opposing the measures to "create the kind of society that's worth living in"
Conservative MP Marcus Fysh came under fire on Monday for comparing the government's plans for vaccine proposals to Nazi Germany.
If the rebellion within Boris Johnson's party becomes so significant that, despite his huge majority, he is forced to rely on Labour, it will be a significant blow to his credibility at a time of widespread anger in his party over his leadership.
The UK registered its first death of a patient who had contracted Omicron on Monday morning, with 1,576 new cases of Omicron reported taking the total number of infections from the new variant to 4,713.