An estimated 1.4 million people in the UK had Covid-19 in the week ending December 16, the Office for National Statistics said.
It is the highest number since comparable figures began in autumn 2020.
In London, around one in 30 people was likely to test positive in the week to December 16 – the highest proportion for any region.
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Last week, a major incident was declared in the capital amid soaring positive cases.
The percentage of people testing positive for Covid-19 in the latest week is estimated to have increased in all regions of England except the North East, south west and West Midlands, where the trend is uncertain, the ONS also said.
Yorkshire and the Humber had the lowest proportion, at around one in 65.
Despite these alarming statistics, on Thursday the Health Secretary ruled out further Covid restrictions in England this week.
