Shoppers should steer well away from store cards unless they can afford to pay off the balance on a monthly basis, a financial expert has warned.

Store card holders are currently forking out as much as £100 million extra in interest and other charges on their branded cards, according to a survey by moneysupermarket.com.

A few outlets including Ikea and Debenhams have now tried to make their deals more competitive but those that take up the offer will end up paying out more than they would on other credit cards.

Many shoppers rarely reap the benefits of the introductory ten per cent offer if they spread the payments over a few months.

Richard Mason, director of credit cards at moneysupermarket said: "Store cards are attractive to consumers at point of sale as they usually offer a discount or introductory offer when you first take out the card."

"If you are making a big purchase, such as a kitchen or a substantial amount of clothes, my advice would be to take advantage of the discount on offer, but it is very important to absolutely ensure you pay the full debt off within the first month of taking out the store card.

"With extortionately high interest rates on most store cards if you are not likely to pay off the debt immediately, it is best to steer clear of them."

But some credit cards on the market can help shop-a-holics. Many offer protection against damage on online purchases and some offer purchase protection meaning that people can claim back the difference if they find the item cheaper somewhere within two months.

Cashback can also mean that shoppers are actually earning money whilst indulging hitting the High Street.