Both campaigns cannot appear in their current forms again with Nationwide's adverts found to be misleading by the Advertising Standards Authority (ASA).

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Katie Price's 755-calorie day ad

Price's post fell foul of rules that require marketing posts to be clearly flagged as ads, as well as health guidelines.

Her promotional video for low-calorie food brand Not Guilty Food had "#ad" as the second last phrase, which the ASA judged was "insufficiently prominent to obviously identify the ad as a marketing communication from the outset".

Ad labels need to be clear and prominent upfront, the ASA said.

But Price's ad hashtag was not visible without engaging with the post and expanding the text, which was insufficiently prominent, it added.

The video, which Price said showed her daily food consumption totalling 755 calories, was also said by the ASA to be "irresponsibly" promoting a diet that fell below 800 calories a day.

Such posts must stipulate diets below 800 calories are only for short-term use and should also encourage viewers to take medical advice before starting them.

The Nationwide complaint - made by a rival

Building society Nationwide's radio, TV and print ads on branch closures - featuring the actor Dominic West as an arrogant bank boss - were said to be misleading as consumers were likely to believe a long-term decision not to close branches had been made and that the lender had not recently closed any branches.

This was not the case, the ASA said.

Instead, Nationwide had promised not to close any more branches before 2026 after having shut two last year.

The 2026 closure caveat was likely to be missed in TV and radio ads, the ASA said.

Rival bank Santander brought the claim to the ASA, a relatively unusual move among British banks. Typically competitors in industries such as retail are more likely to make formal complaints.

Santander had been used as a comparative "big bank", which the ads said were closing branches.

In an ad campaign the year before, Santander said it had closed fewer branches than Nationwide and at the time the ad was seen it had not announced future closures.