Secondary school children across the south east will be urgently tested to bring down rising coronavirus cases.
During a Downing Street press conference, Matt Hancock said the fastest rise is among 11-18 year olds.
There are especially high numbers in positive infections across London, parts of Essex and parts of Kent.
The health secretary said it isn't possible to wait until the review and mobile testing units will be deployed.
He said: "We know from experience that a sharp rise in younger people can lead to a rise in vulnerable age groups later.
"We cannot wait until the review on December 16.
"The immediate plan is to test secondary school kids - including those without symptoms - in the worst affected areas with mobile testing labs."
They will be testing all secondary school aged children in the seven worst affected London Boroughs, parts of Kent and Essex.
Mr Hancock urged this is to keep schools open.
