The motorist, driving a blue Citroën, was said to have lined up at the Shell garage in Welling, south-east London, when he was stopped by a passenger queuing in another car.
The other drivers stayed inside their car as the man walked towards the vehicle holding a knife before being thrown on the hood on Monday afternoon.
The man reportedly claimed he had been lining up for gas since 8 a.m. but was turned back because the forecourt was empty, then returned looking determined to get to the pumps.
It comes after retailers said up to 90% of their outlets in and around London were running out of petrol and diesel after a six-fold increase in demand from drivers over the weekend .
Stefan Silva, 29, an engineer from Kent, was among the motorists who witnessed the chaos in Welling.
He told The Standard, “He tried to jump in line, basically.
“The man was screaming and saying ‘I’m going to slice it. Everyone has been in line for hours. Why don’t you stand in line? “
“The man kicked the car and destroyed his rearview mirror.
“Everyone was in the same situation, but the guy said he got there first at 8 am and said to come back at 1 pm after the next fuel delivery.
Mr Silva said the man with a knife fled the scene on foot when he intervened.
“He still had the knife in his hand and I called him,” he said.
“I said to him ‘don’t bother stabbing someone to try and get some fuel.’
“I calmed him down and that’s it.
“Everyone stayed in their car. I think they were more concerned with getting the fuel themselves.
Police confirmed officers were called to report a disturbance involving two motorists outside a petrol garage in Bellegrove Road at 2:37 p.m.
A spokesperson said: “Officers attended and found no sign of either vehicle. No injuries were reported and no suspects were identified.
“We are aware of footage online that appears to show the incident and will be reviewing it as part of our ongoing investigations. “
Fighting has been reported at petrol stations across London as forecourts run out of fuel due to a shortage of truck drivers.
Images on social media show a scuffle between drivers at a gas station in Camden, north London, on Sunday.
Motorists face huge queues at pumps across the country due to panic buying and a shortage of truck drivers delivering fuel and goods.
Thousands of Londoners, including doctors and teachers, were forced to work from home on Monday as the capital suffered the brunt of the “chamber” fuel crisis.
Black London cab drivers have called on the government to introduce essential user-only service stations.
Police were forced to skip the line for gasoline in Hackney as an ambulance on a blue light call came across a motorist as it attempted to pass another queue in Bromley during of the weekend.
Drivers had been warned that they could break the law by storing gasoline with the Health and Safety Executive warning that they can only legally store 30 liters at home without notifying the proper authorities.
The rules state that only 20 liters of gasoline can be stored in a metal jerry can at home, whether in a shed or garage, while 10 liters can be kept in alternative plastic containers.
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