Police and petrol companies have urged motorists not to panic-buy fuel after the explosions at the Buncefield depot.
As reports come in of long queues at petrol stations, authorities said there were sufficient alternative supplies for London and the South East.
"I understand the concern of motorists, but there is no need to panic," said Ray Holloway of the Petrol Retailers Association.
"This site is strategically important, but not critically important."
"There will be no market effect and the oil industry will do what it does and manage this extremely effectively."
The Buncefield site may be a main supplier for the South East and London regions, but there were a number of other depots and storage facilities that would be able to fill the gap, authorities said.
These include facilities in Reading, Northampton and east London.
Sheila Williams, spokeswoman for oil giant BP, said there would be no problems with fuel shortages.
"There is certainly no shortage of fuel in and around the area and we are working hard to bring fuel supplies in from other terminals to petrol sites in those areas affected," she said.
"Companies like BP can bring supplies via tankers from other areas.
"People shouldn't be concerned."
Hertfordshire Police said panic-buying would be very unhelpful.
"We have no indication at this stage that this explosion will cause fuel shortages," said a spokeswoman for the force.
"We strongly advise against this as recent events have shown that panic-buying alone can cause fuel shortages."
A spokesman for the Department for Trade and Industry said it was working closely with the UK Petroleum Association.
"It is too early to say what the exact effect of the fire will be on the supply of fuel but oil companies are already making arrangements to source oil products from the many other locations in the south east and across the UK," he said.
"We understand that the oil industry is meting this afternoon to determine how the supply of petroleum products can be augmented from other distribution terminals."
Buncefield also supplies fuel to major airports including nearby Luton and Heathrow.
Both said they held sufficient supplies to avoid any disruptions.
"There is no indication that there will be a shortage in the foreseeable future," a Heathrow spokeswoman said.
Yet some flights had been cancelled at Heathrow as a result of smoke from the fire.