The rate of cases in London is reported to have increased from 18.8 per 100,000 people to around 25 in a seven-day period ending early last week.
The mayor’s office said London’s case rates were catching up to those in Covid hotspots in the north-west and north-east of England, where strict controls have been placed on social gatherings.
Mr Khan is ready to “recommend” curbs on movement in London to the government if necessary – and asking commuters to work from home has not been ruled out.
The mayor’s spokesperson said on Sunday: “The situation is clearly worsening. Sadiq will meet council leaders tomorrow and any London-specific measures will be recommended to ministers following that.
“The mayor wants fast action as we cannot risk a delay, as happened in March. It is better for both health and business to move too early than too late.”
It comes as Mr Khan urged ministers to extend the latest regional restrictions, including ordering bars and restaurants to close at 10pm, to cover the capital as well.
Health secretary Matt Hancock admitted the introduction of new lockdown restrictions in London within days was under discussion.
Mr Hancock said he had spoken with Mr Khan over the weekend about what action is needed in the capital.
Asked if London office employees could be advised to work from home from some point next week, Mr Hancock told Times Radio: “Well, I wouldn’t rule it out.”
Such a move would clash with the government’s recent messaging, which has been to urge people to return to their offices following the easing of lockdown restrictions.
The government’s chief medical officer and chief scientific officer for England are expected to warn that Britain is at “critical point” in the pandemic, as the number of new cases continues to rise.
Professor Chris Whitty will lead a televised briefing alongside Sir Patrick Vallance at around 11am on Monday morning, where they will potentially lay the ground for Boris Johnson to bring tough new national controls in a bid to control the spread of Covid-19.