Price comparison sites have accused Google of failing to comply with an EU ruling demanding it give other shopping services "equal treatment".

The accusation comes in a letter from 14 rivals to the European commissioner for competition, Margrethe Vestager, who fined Google a record €2.4bn (£2.14bn) for anti-competitive practices in June 2017.

At the time, she ordered the company to restore competition on its platform - something which the rivals say still has not happened.

In the letter, the group of European sites wrote: "The harm to competition, consumers and innovation caused by Google's illegal conduct has continued unabated."

In September 2017, three months after the commission's verdict, Google announced that it would allow rivals to bid against its own service in the auction for advertising slots on Google Shopping, which features these ads as an insert at the top of product searches.


Image: Google Shopping allows competitors to bid for ad space

However, the price comparison sites say that take-up of the scheme was poor because the auction model requires them to bid away all their profit.

Sky News revealed last month that Google was offering substantial incentives to advertising agencies to create price comparison sites, giving the illusion of competition on its platform.

However, several site operators told Sky News the comparison shopping services (CSS) were never intended for consumers to use - a revelation that prompted questions in the European parliament.

Google retreats on 'fake' price comparison site scheme

"Presumably, realising that it will never be possible to populate its new auction with enough genuine comparison shopping services to create even the veneer of a functioning remedy, Google has now set about populating it with fake ones instead," the price comparison sites wrote.

The 14 price comparison sites include Acheter-moins-cher.com, PriceRunner, Idealo and Foundem, the company which initially brought the original complaint against Google in 2010.

If Google fails to comply with the commission's decision, it would be liable for non-compliance payments of up to 5% of the average daily worldwide turnover of Alphabet, Google's parent company, backdated to the start of the non-compliance.

A Google spokesperson told Sky News: "We've complied with the European Commission's order. We allow all comparison shopping services to compete equally to show product ads from merchants on Google's Search results page.

"To help drive awareness amongst merchants who are unfamiliar with these new opportunities, we're currently offering incentives for them to work with comparison shopping services. One year on, both services that existed before the remedy and services that are new to comparison shopping are participating successfully."