Google has offered the Financial Conduct Authority (FCA) three million dollars (£2.2 million) in free credits to advertise anti-fraud services and consumer protection advice, the company has revealed.

But the search engine giant refused to reveal how much the financial watchdog has spent advertising on its platform previously, despite requests from MPs for the information.

Officials at the financial regulator had been critical of tech giants that have taken money from unscrupulous firms for paid-for advertising, then further cash from the FCA for advertising against them.

MPs on the Treasury Select Committee asked Google and Facebook how much they received in advertising and what actions they are taking to avoid unregulated products featuring in paid-for slots.

Facebook declined to say whether it would stop taking cash for adverts from regulated financial products not authorised by the FCA.

Meanwhile, Google said it had implemented a voluntary system to only advertise FCA-approved services, although there are exemptions for cryptocurrency or debt services.

MPs were keen to see if the services would refund the FCA money spent on advertising, but neither would confirm they would.

The companies, alongside Amazon and eBay, appeared before MPs last month and were questioned on whether they agreed with the FCA that the Government’s Online Safety Bill should extend to pay-for advertising and user-generated content to crack down on fraud.

On Friday, letters from the companies clarifying how they are tackling online fraud were published.

At their appearance, executives at the firms told MPs it would be difficult to implement and said they were already implementing measures to improve fraud detection.

An FCA spokesperson said: “The FCA remains in discussion with Google about its offer to provide ad credits to off-set the future spend by the FCA educating consumers about online harms, including through our ScamSmart campaign.

“We are talking to a number of online search and social media companies about how they can protect their users from exposure to online financial harm, including that caused by the placement of unauthorised financial promotions.

“We also want to see investment fraud to be included in the Online Safety Bill so that consumers can be better protected from scammers and fraudulent advertising.”