The figure for the week ending 31 December was up from 2.3 million in the week to 23 December. It marked the highest number since comparable figures began in autumn 2020.

According to the latest ONS infection survey, an estimated one in 15 people in England had COVID in the week up to 31 December.

This is the equivalent to 3,270,800 people.

The new figures also show it was as many as one in 10 in London.

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In Scotland and Wales, an estimated one in 20 people had the virus, while in Northern Ireland the figure was one in 25.

All estimates are for people in private households and do not include hospitals, care homes and other settings.

Record number of daily COVID cases in UK

It comes as a record number of daily COVID-19 cases - more than 218,000 - were recorded in the UK on Tuesday, with the highly transmissible Omicron now the dominant variant in the country.

However, the reporting of some of those cases had been delayed due to a lag over the festive period.

Cases were down slightly on Wednesday to 194,747.

Meanwhile, Boris Johnson has led a cabinet meeting where he recommended sticking with England's Plan B despite the record infection numbers and increasing pressure on hospitals, with several NHS trusts declaring critical incidents.

The Plan B measures, which will be reviewed before they are due to expire on 26 January, include work-from-home guidance, mask-wearing and COVID health passes.

'Chance to ride out Omicron wave' - PM

At a news conference on Tuesday, the prime minister argued the vaccine booster rollout has given people substantial protection and claimed: "We have a chance to ride out this Omicron wave without shutting down our country once again."

Mr Johnson accepted the coming weeks were going to be "challenging" and said "some services will be disrupted by staff absences" as he pledged to "fortify" the NHS to withstand the pressures and protect supply chains.

And in the Commons on Wednesday, the PM said "this will unquestionably be a difficult period for people".

PCR test announcement

Also, people in England who test positive on a lateral flow device will no longer need a follow-up PCR to begin their isolation period if they do not have symptoms, the UK Health Security Agency has confirmed.

The change, which will take effect from 11 January, comes after health minister Gillian Keegan told Sky News that "around a million people" are currently isolating as a result of COVID.

Wales will also scrap confirmatory PCR tests for asymptomatic people.

The moves will free up capacity in laboratories for PCR tests for those who have COVID symptoms.

It's also been announced that pre-departure testing will no longer be required for travellers returning to the UK, and arrivals will not have to isolate until they get a negative PCR test.

Scotland COVID isolation period cut

In Scotland, Nicola Sturgeon has announced the coronavirus isolation period is to be reduced from 10 days to seven.

The change comes into effect from midnight and brings the nation broadly in line with the rest of the UK.

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People will be able to leave their isolation after seven days provided they test negative on lateral flow tests for the last two days and have no fever.

They will be asked to take a lateral flow test no earlier than day six and a second test at least 24 hours later.