Fraudsters can create and post adverts for fake businesses on Google “within hours”, according to a Which? investigation.

News of its findings comes weeks after the Advertising Standards Authority announced it was launching a UK “scam ad alert” system in partnership with platforms including Facebook and Google, “to help tackle bogus ads”.

Which? created two linked fake companies – a water brand named Remedii that “can help you lose weight [and] improve your mood”, and an online service offering “pseudo health and hydration advice” called Natural Hydration.

The consumer body said Google only required users to have a Gmail account to create adverts and that, while it did review those that were submitted, it did not verify whether the business existed or was legitimate, nor ask for proof of ID.

In less than an hour, the ads Which? created for both fake businesses were approved by Google. They racked up nearly 100,000 impressions in a month. The fake ad for Natural Hydration appeared above the official NHS Scotland pages when users searched for “hydration advice”