Morrisons is offering shoppers 10p off each litre of fuel purchased at its petrol stations, but there are a couple of catches: it's only until Sunday November 26 and you need to spend in store to be eligible.

The discount is running as part of the supermarket's BlackFiveDays promotion and is open to anyone who spends £50 or more in-store between now and Sunday. And yes, it applies to diesel and unleaded.

You'll get a voucher in-store which is valid until December 3, so you won't miss out if you don't top up your tank by the end of the week. Just be aware that you can't redeem vouchers at Texaco, BP and Esso outlets.

Steve Mosey, Morrisons services director, said: “Motorists could face a triple-whammy of rising petrol prices, extra fuel tax and a busy Christmas shopping season so we’re doing what we can to help them afford to run their cars.”

This is welcome news as experts at Nomura predict that the price of fuel could shoot up by 7p-8p in the coming weeks.  

Do your research before filling up

It's a good idea to check if you're getting a good deal before filling up.

If you're not a regular Morrisons shopper, it might not be worth doing a £50 shop for a fiver off a 50-litre tank fill-up. You could be better off going to your regular petrol station and getting cheaper groceries elsewhere.

The price you pay at the pumps will vary depending on where you live.   

There are even greater variations depending on which specific fuel station you choose to fill up at.

Make sure you do your homework to find the cheapest station in your area. You can do this easily enough by entering your postcode on PetrolPrices.com and comparing prices nearby.

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