The fuel crisis in south east England remains 'absolutely horrendous' with some desperate motorists saying most forecourts are now dry.
Industry leaders have issued a warning as panic-buying continues with petrol prices set to soar.
On Monday, Army personnel will start delivering fuel as Petrol Retailers Association chairman Brian Madderson says the issue is now getting out of hand.
Motorists - already angry at being unable to fill up in parts of the UK - are being told prices could rise by up to 5p a litre this week
It comes as Boris Johnson admits he has known for months that the UK's haulage industry was in trouble, as he indicated the supply chain problems besetting the economy could continue until Christmas.
Madderson said there were only "one or two dry sites" north of London and that the "general improvement has continued" - but that the situation in London and the south east remained very challenging.
Speaking to Sky News, he said: "It's all really to do with the population, we have 25 million-plus living in and around London and the home counties.
"Early signs from our polls this morning show again that the Midlands, North and Scotland, are doing pretty well, and more and more of their filling stations are getting stock.
"There is far less stock out and far less surge buying. Normality is creeping in to that party of the country, but London and the South East are absolutely horrendous."
He added on LBC: "London and the South East seems to be really awful. I had one of my retailers from Bracknell ring me this morning, saying all six sites - including the two supermarkets - are out of fuel."
On the opening day of the Tory Party conference in Manchester, the Prime Minister insisted the fuel crisis is "abating" despite continuing reports of long queues for petrol in some parts of the country.
However, he acknowledged the UK economy is facing "stresses and strains" as it moves away from the "broken model" which, he said, had been rejected by voters in the 2016 Brexit referendum.
But Mr Johnson insisted he will not solve the issues in the labour market - which have led to warnings of shortages on the shelves in the run-up to the festive season - by pulling "the big lever marked uncontrolled immigration" to allow in large numbers of foreign workers.
Asked on the BBC's The Andrew Marr Show about a warning by Chancellor Rishi Sunak that shortages could continue to Christmas, Mr Johnson said: "Rishi is invariably right in everything he says."
He then added hurriedly: "It depends how you interpret what he is saying."
In comments made later on Sunday during a visit to a youth centre in east Manchester, Mr Johnson said he would keep "all options on the table" to fix the delivery difficulties being witnessed, but stressed industries would also have to step up.
He told broadcasters the haulage sector would need to invest in "better truck stops" in order to attract a more diverse workforce, including women lorry drivers.
Pressed on whether there could be more temporary visas issued to prevent empty supermarket shelves, the Conservative Party leader said: "We'll take each step as it comes, we're there to support industries that are having difficulties.
"But it is fundamentally up to them to work out the way ahead.
"In the end, those businesses, those industries, are the best solvers of their own supply chain issues - Government can't step in and fix every bit of the supply chain.
"But what we certainly will do is keep all options on the table."
The PM was also pressed on a warning given by the Road Haulage Association which wrote to him in June saying a major crisis was building in the industry due to the shortage of HGV drivers.
The Prime Minister said: "We have known about shortages in road haulage long before then. They have been a chronic feature of the way the road haulage industry has worked."
Mr Johnson said the problem at the forecourts - triggered by reports that a shortage of tanker drivers was affecting deliveries - is "fundamentally one of supply".
He said the economy faces a "period of adjustment" and the way to get more HGV drivers is for the industry to ensure they are "decently paid".
His comments come as military drivers prepare to take to the roads for the first time on Monday in support of the operation to keeping filling stations supplied.
Around 100 trained drivers with an additional 100 support troops are due to be deployed over the coming week, despite repeated assurances by ministers the situation is "stabilising".
