Sainsbury's is wooing motorists with the eye-catching offer of petrol at less than £1 a litre.
Shoppers who spend £30 or more in store or online will be given a voucher worth 10p a litre off the standard price. And with all the company's stores currently selling unleaded petrol at 109.9p a litre or less, that brings the price below the magic figure.
It means, says Sainsbury's, that anyone driving a family saloon using unleaded fuel will pay £12.44 less to fill up than they did this time last year.
But customers will have to hurry, with the offer ending next Wednesday, March 4.
"We're delighted to be offering customers this super saving on fuel. For the cost of their essentials, they can take advantage of some of the biggest fuel savings in the market," says Sainsbury's retail and operations director, Roger Burnley.
"Customers can fill up at nearly 300 petrol stations at our stores straight after their shop."
The offer is a pleasant surprise for motorists, who have seen the price of petrol start to creep back up lately. While the price of oil recently reached a five-year record low, it's recently started to rise again.
As a result, forecourt prices have started to go back up again too: last week, says the AA, some petrol stations were adding a penny a day.
All the same, last week, unleaded was averaging 108.328p, still marginally lower than the mid-January average of 109.91p. Diesel was down from 116.11p to 115.06p.
"There is hope that the price of oil will settle back to around 50 dollars a barrel," said AA president Edmund King.
"However, the lesson of 2009 is that, apart from a short period of falling prices in the summer, the cost of petrol maintained a gradual climb through to the May of 2010."
And Mark Carney, the governor of the Bank of England, last week warned that motorists couldn't expect low prices to stay.
"This is a temporary phenomenon, so enjoy it while it lasts," he told MPs. "Petrol prices aren't going to continue to fall, food prices aren't going to continue to fall."
According to data compiled by Experian Catalist for The Sun, the supermarkets are doing a better job of keeping prices down than the big petrol companies such as BP and Shell - all part of the price war that's keeping down grocery prices too.
Read more on AOL Money:
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Big supermarkets reduce fuel again
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