London is just “days away” from a lockdown that could see restrictions reimposed and commuters working from home, Sadiq Khan has said.
The Mayor believes the capital could be just two or three days behind hotspots in the North West and North East of England.
He has called on the Government to impose restrictions on bars and restaurants and is planning to tell Londoners to work from home.
The number of cases per 100,000 people over seven days is reported to have increased in London from 18.8 to around 25 earlier in the week.
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Asked if Londoners could be told to work from home, Matt Hancock, the Health Secretary, said: “I wouldn’t rule it out”.
Mr Hancock said he was "very worried" about the latest data which suggested Britain could be on the same path as Spain and France - where deaths and hospitalisations are increasing - without effective action.
"I am very worried about this second wave. We have seen in other countries around Europe how it can absolutely shoot through the roof," he said.
London council sources suggested the mayor could go beyond new Government guidance expected to be issued this week by telling commuters to stay at home.
Such a move would be in contrast to the Government's recent messaging, which has been urging people to get back to their offices following the easing of lockdown restrictions.
A mayoral source said: "It's clear that cases in London are only moving in one direction, we are now just days behind hotspots in the North West and North East. We can't afford more delay.
"Introducing new measures now will help slow the spread of the virus and potentially prevent the need for a fuller lockdown like we saw in March, which could seriously damage the economy once again."
Mr Khan told Labour's virtual conference on Sunday: "Unfortunately, and it gives me no pleasure to say this, we've all been catastrophically let down by the Government.
"If ministers had risen to this moment, as the British public have, then the loss of many lives and much of the economic hardship could have been avoided.
"These times called for a government that could put ideology, dogma and ego aside, and calmly and competently do whatever it takes to save lives and jobs.
"Unfortunately, we got the exact opposite. Just when we required a steady, capable hand on the tiller, we've had a hapless government that keeps on steering us onto the rocks."
Any new restrictions will be met with opposition from some Tory backbenchers, who are concerned that ministers are taking increasingly stringent powers with little or no parliamentary scrutiny.
Sir Graham Brady, chairman of the powerful Tory backbench 1922 Committee, said he intends to table an amendment which would require the Government to put any new measures to a vote of MPs.
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He told The Telegraph that he would take the opportunity to seek to amend the legislation when the Government comes to renew the emergency powers in the Coronavirus Act 2020.
"In March, Parliament gave the Government sweeping emergency powers at a time when Parliament was about to go into recess and there was realistic concern that NHS care capacity might be overwhelmed by Covid-19," he said.