Consumer expert Martin Lewis has issued a warning to shoppers ahead of Black Friday. 

The money saving guru and finance journalist appeared on his ITV show, the Martin Lewis Money Show, telling people they may be losing money on Black Friday deals.

He said shoppers could be losing cash when buying things reduced in the sales.

According to Mr Lewis, you'd be losing money because the chances are your buying something you wouldn't have bought if it weren't on sale.

He said: "Let's take the basic premise of any discount. If you were planning to buy a video game for £50 and it's on sale for £25 you've saved 25 quid.

Southend Standard: Money saving expert Martin LewisMoney saving expert Martin Lewis

"If they have tweaked your spending nipples to buy something you wouldn't otherwise buy, there's an extra cost of £25, so it's not a saving.

"So that's the first premise."

He added: "I've never liked these 'oh we have one TV, 50 in stock for a tenner instead of £1,000' - that's a competition.

"Where it's useful is, you've got a list, you know what you want, you create your list, and stores have store-wide discounts which means you can buy it 30 per cent cheaper."

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Despite his comments, Mr Lewis did admit Black Friday is the best time to get your Christmas shopping done.

He said: "This is likely, in many cases, the cheapest time to buy before Christmas."

What is Black Friday?

Black Friday takes place every year the day after Thanksgiving and is a day when many stores introduce new offers, encouraging customers to buy more.

This year due to the coronavirus pandemic, many department stores will close their doors on Thanksgiving night and encourage shoppers to buy online on Black Friday to curb the spread of the virus.

Why is it called Black Friday?

The day was given its name as it is often the day that shops "move into the black", meaning they have enough money to cover their costs while reducing prices.

In the UK the name traditionally refers to the Friday before Christmas, which is when police and NHS emergency services anticipate extra pressures put on them due to festive celebrations.

However, since 2014 the term has become more associated with the huge shopping event.

It is well known among shoppers as a day of bargains which has come across the pond from the US since the beginning of the 21st century.