The ASA said the adverts “trivialised investment in cryptoassets and took advantage of consumers’ inexperience”.

The adverts were for $AFC fan tokens. A Facebook post and website for Arsenal Football Club encouraged fans to download the Socios app, buy a token with cryptocurrency Chiliz and then vote on club matters. The ad included a video featuring footballers Ben White, Calum Chambers and Kieran Tierney.

An NFT is essentially a digital asset – it can be a token, an artwork, a piece of music or an item or character known to the gaming community – that can be created, bought or sold, much like similar assets in the real world.

The ASA challenged whether the Arsenal ad was misleading “because it did not make clear that the tokens were cryptoassets, which could only be obtained by opening a cryptoassets exchange account, and in the case of paid-for fan tokens, required the purchase of another cryptocurrency”.

The ASA also said that the ads were irresponsible “because they took advantage of consumers’ inexperience or credulity and trivialised engaging with and investing in cryptoassets”.

The complaints were upheld as the ads only referred to fan tokens as a “token” and didn’t include warnings about the risks associated with cryptoassets despite the fact that fans had to purchase cryptocurrency Chiliz to buy a fan token.

The ASA said this approach meant that “consumers were unlikely to understand that the ad referred to cryptoassets”. It also criticised the risk warning on the advert for not stating that paid-for fan tokens were cryptoassets which were unregulated in the UK.

Susannah Streeter, senior investment and markets analyst at Hargreaves Lansdown, said: “It’s not the first time the ASA has censured the club for its crypto promotions. Late last year it banned the club’s posts on Facebook and its website which promoted ‘fan’ tokens as they took advantage of consumers’ inexperience in crypto assets and misled consumers by not making it clear that these NFTs had to be bought using another cryptocurrency.”

NFTs, which have been described as “modern day trading cards”, are seen as valuable streams of fresh revenue for football clubs, and for soccer stars who have been promoting other schemes.

But with the value of crypto coins and tokens crashing in spectacular fashion in the last few months, as a wave of anxiety gripped financial markets, it’s left many hopeful fans in the stands clutching NFTs with hefty losses.

Streeter added: “ASA officials are faced with the task of running the line, assessing every complaint against companies, but with scant other regulation governing crypto assets, and so many flags springing up it’s becoming an increasingly difficult play to monitor. This ruling is another stark reminder that people should resist ploughing money into schemes they don’t fully understand and should only speculate with money they can afford to lose. It also highlights the need to speed up the plan to give the city watchdog – the Financial Conduct Authority more powers to regulate the crypto industry, given the government’s vision to make the UK a crypto hub.”