Hundreds of social media posts and websites operated by financial influencers are to be taken down following action by the City regulator.

The Financial Conduct Authority (FCA) said the move was part of an international crackdown, which has led to three arrests in the UK.

So-called finfluencers can legitimately give financial tips on social media to large audiences, but sometimes this can stray into illegal financial advice.

That can include a lack of authorisation and a failure to explain the risks – all packaged in promotional posts using the pretence of a lavish lifestyle.

Regulators across across the UK, Australia, Canada, Hong Kong, Italy and the United Arab Emirates were involved in the crackdown during the week.

The FCA said that, in the UK, it resulted in 650 requests for deletions from social media, and 50 take downs of websites operated by unauthorised finfluencers.

It has also sent seven “cease and desist” letters, and invited four finfluencers for interview.

Steve Smart, from the FCA, said: “Our message to finfluencers is loud and clear. They must act responsibly and only promote financial products where they are authorised to do so – or face the consequences.”

There are strict rules surrounding authorisation requirements for financial promotions in the UK. In some cases these are flouted, according to Beth Harris, head of financial crime at the FCA.

“The typical thing you may see is that somebody with a large social media presence will be on a beach in a sunny location with some super cars behind them, and wearing designer clothes and basically trying to sell a lifestyle,” she told the BBC’s Today programme.

“Often they’ll say they have super algorithms that means that they are a wonderful trader, so that then you can pay a fee, and then they will send you their trade.”

However, to do this, she said, “you must be authorised”.

The FCA can request that social media platforms take down certain content, but the regulator has no powers to enforce them to do so.

It called on these platforms to act on its requests quicker.

The plea comes as the Treasury Committee has written to the technology company Meta – the owner of Facebook and Instagram – questioning its response to this kind of harmful content.

The committee has asked Meta to set out to it why “it has taken you on occasion up to six weeks to respond to a takedown request from the Financial Conduct Authority?”

A statement from Meta regarding the committee’s letter said: “There was an isolated incident in late 2024 which resulted in a delay in actioning a small number of reports from the FCA. This was rectified and all other relevant reports made by the FCA have been promptly processed.”

On Tuesday, the MPs on Treasury Committee will quiz the chief executive of the FCA, Nikhil Rathi, on moves to bring more cryptoasset activity into regulation.

On Friday, the regulator said it was proposing to lift the ban on offering crypto exchange traded notes to retail investors.

This would allow individual investors to put money into products that track the value of crypto.

The ban has been in place since 2021.