Schools in the London borough of Greenwich are set to shut from Monday after coronavirus cases saw an "exponential growth", it has been confirmed.
The case rate in Greenwich has surged to over 200 cases per 100,000 which is higher than the national average and the spike "demands immediate action", the council has been told.
All 133 schools across the borough will now close on Monday instead of on Thursday, which was meant to be the last day before term ends for the Christmas holidays.
The news comes as London could move into Tier 3 restrictions when the situation is reviewed on Wednesday.
Public Health England advised Greenwich council to shut schools early because the coronavirus situation was escalating "extremely quickly", said council leader, Danny Thorpe, in a statement.
Cllr Thorpe said in an open letter: "The situation in Greenwich in relation to Covid-19 is now escalating extremely quickly.
"I have today been briefed by colleagues from Public Health England that the pandemic in Greenwich is now showing signs that we are in a period of exponential growth that demands immediate action.
"We now have the highest rates of infection in Greenwich than at any time since March.
"For these reasons, I have therefore asked all schools in Greenwich to close their premises from Monday evening and move to online learning for the duration of the term, with the exception of key worker children and those with specific needs (exactly the same as in the first lockdown)."
Greenwich is the 14th highest borough in London for coronavirus cases. Havering in East London is the worst affected borough at the moment with a rate of 470.8 cases per 100,000 people.
It's uncertain at the moment whether other London boroughs will follow Greenwich's lead.
It's claimed that Tory MPs are urging Boris Johnson to split London up in terms of tiers.
Health Secretary, Matt Hancock, may consider moving London's worst-affected boroughs on the outskirts into Tier 3, the highest level of restrictions, and leaving the centre in Tier 2 so businesses aren't affected as badly.
They said putting all of London into Tier 3, where pubs and other hospitality and entertainment venues would have to close, could cause a £3 billion hit to the economy.
