Lodon. A legal adviser to the European Union's top court said Thursday that Google should pay a whopping fine in a long-running antitrust case in which regulators found the company gave its own shopping recommendations an illegal advantage over rivals in search results.

The European Court of Justice's advocate general, Juliane Kokott, recommended rejecting the US search giant's appeal of the 2017 penalty. In a legal opinion, Kokott also proposed upholding the 2.4 billion euro ($2.6 billion) fine that the European Commission, the 27-nation bloc’s top competition watchdog, slapped on Google.

The commission had accused the company of unfairly directing visitors to its own Google Shopping service to the detriment of competitors. It was one of three multibillion-euro fines that the commission imposed on Google in the previous decade as Brussels started ramping up its crackdown on the tech industry.

Google appealed to the top EU tribunal after the lower General Court rejected its challenge. Opinions by the Court of Justice's advocate general aren’t legally binding but are often followed by its judges. Their final decision is expected within months.

“Google, as found by the Commission and confirmed by the General Court, was leveraging its dominant position on the market for general search services to favor its own comparison shopping service by favoring the display of its result,” the Court of Justice said in a press summary of the opinion.

This “self-preferencing” amounts to "an independent form of abuse” by Google, it said.

Google has previously said it made changes in 2017 to comply with the European Commission’s decision.

“We will review the opinion of the Advocate General and await the final decision of the court," Google said in a statement. "Irrespective of the appeal, we continue to invest in our remedy, which has been working successfully for several years, and will continue to work constructively with the European Commission.”

The commission declined to comment.