Schools in Greenwich have been asked to close and switch to remote learning from Monday evening due to rising coronavirus rates in the borough.

In a letter to parents on Sunday, Greenwich Council leader Danny Thorpe said the south London borough was experiencing a period of “exponential growth” in Covid-19 cases, which required “immediate action”.

He said infection rates were now at their highest since March, adding that the move was aimed at reducing the risk of further transmission.

Thorpe said: “I wouldn’t be asking for this unless the risk was extreme, but with numbers rising so rapidly it is clear action is needed.”

He added: “Although London is currently in Tier 2, this is being reviewed by the government who will advise us shortly about the decisions they make.”

The government has said it will review all tiers in England on December 16.

Thorpe stressed that the school closure was not an opportunity for parents to extend Christmas celebrations.

He said: “We now have the highest rates of infection in Greenwich than at any time since March, and 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).”

The latest data shows there were 715 new coronavirus cases recorded in Greenwich in the seven days to December 9 – the equivalent of 248.3 cases per 100,000 people.

This is up from a rate of 158.0 in the seven days to December 2.

The figures have been calculated by the PA news agency, based on Public Health England data published on December 13 on the government’s coronavirus dashboard.

In a separate letter to headteachers, Thorpe said the latest data suggested the rate of infection in London was doubling every four days.

Speaking about the decision to close schools, he said: “This is honestly one of the most difficult questions I have wrestled with during all my time as leader.

“The Department for Education are clear this isn’t their position and indeed have issued directives to some schools.

“However, I cannot in all good conscience stand by whilst the numbers are doubling so quickly.

“If the numbers are indeed doubling every 4 days, they would do so again by this Thursday, exposing more people to risk.”

Schools in England have been warned they could face legal action if they allow pupils to learn remotely in the run-up to Christmas.

New powers introduced through the Coronavirus Act allow the government to issue “directions” to head teachers around education provision during the pandemic.

But should schools fail to comply with directions to remain open, education secretary Gavin Williamson could apply for a High Court injunction forcing them to do so.

The Department for Education (DfE) said keeping education settings open remained a “national priority” and that it was “vital” children remain in school until the end of the term.

In Wales, secondary schools and colleges will move to online learning from Monday following advice from the Welsh chief medical officer that the public health situation in the country is “deteriorating”.