A vehicle marked with a Transport for London private hire car licence roundel was caught reaching speeds of up to 96mph in the capital.
The driver was clocked by Neal Donohoe, an Inspector in London's Metropolitan Police force, and part of the East Roads Policing Team.
The offence occurred on the A406 North Circular road, which runs from Chiswick, West London, to Beckton in the East.
Using his official Twitter account to highlight the offence, Donohoe @NealDonohoe, said: "You're much more likely to cause serious injury with excess speeds.
"We are still seeing high levels of traffic and speeding despite a lockdown. Collisions further impact on our already stretched NHS.
"We still have mandate to make our roads safer. Slow down."
Donohoe had originally said the incident happened on the A13, but later confirmed that the driver committed the offence while driving on the A406, North Circular road.
Transport for London, as a licensing authority, are now likely to consider whether the driver, if a current private hire driver, is still a fit-and-proper person to hold a licence.