Around two-thirds of recent positive cases in London, eastern England and south-east England could be the new variant of Covid-19, the ONS found.
In London, 68% of positive cases from December 14 to 18 were estimated to be genetically compatible with the new variant, while in eastern and south-east England the estimate is 65%.
For England as a whole, the ONS estimated 49% of new cases could be the new variant.
All figures are for people in private households, and are subject to revision.
