Google has been hit with a record fine of 2.42 billion euros (£2.1 billion) by Europe's competition watchdog after breaching antitrust rules with its online shopping service.
The European Commission said the tech giant had abused its market dominance as a search engine by handing an "illegal advantage" to its comparison shopping operation.
In a statement, commissioner Margrethe Vestager said: "Google has come up with many innovative products and services that have made a difference to our lives.
"That's a good thing. But Google's strategy for its comparison shopping service wasn't just about attracting customers by making its product better than those of its rivals.
"Instead, Google abused its market dominance as a search engine by promoting its own comparison shopping service in its search results, and demoting those of competitors."
The watchdog launched an investigation into Google Shopping seven years ago amid complaints it gave the service a prominent position on the internet search engine, while rival services were demoted.
Google now has 90 days to stop the practice or face a penalty of up to 5% of the average daily turnover of the firm's parent company, Alphabet.
Ms Vestager added: "What Google has done is illegal under EU antitrust rules. It denied other companies the chance to compete on the merits and to innovate.
"And most importantly, it denied European consumers a genuine choice of services and the full benefits of innovation."