European antitrust regulators have fined Google a record 4.34 billion euros ($6.8b) and ordered it to stop using its popular Android mobile operating system to block rivals, a ruling the US tech company says it will appeal.
The penalty is nearly double the previous record of 2.4 billion euros which Google was ordered to pay last year after its online shopping search service was deemed to be unfair to competitors.
It represents just over two weeks of revenue for Google parent Alphabet Inc and would scarcely dent the company's cash reserves of US$102.9b (A$139b). But it could add to trade tensions between Brussels and Washington.
European Commission President Jean-Claude Juncker is due to meet US President Donald Trump at the White House next Wednesday in an effort to avert Trump's threatened new tariffs on cars made in the European Union as the president looks to reduce the US trade deficit.
Alphabet, which is scheduled to report financial results on Monday, said it would set aside money to pay the fine which would cut its second-quarter profit by about $5 billion. Wall Street analysts were expecting $6.8 billion in quarterly profit on average before the fine.
Alphabet shares closed flat on Wednesday after technology analysts said the EU order would do little damage to the company's long-term prospects.
Google's Android system, which Google lets device makers use for free, runs about 80 per cent of the world's smartphones, according to market research firm Strategy Analytics.
According to the EU, Google's illegal behaviour dates back to 2011 and includes forcing manufacturers to pre-install Google Search and its Chrome browser together with its Google Play app store on their Android devices, paying them to pre-install only Google Search and blocking them from using rival Android systems.
"Google has used Android as a vehicle to cement the dominance of its search engine" over rivals, EU antitrust chief Margrethe Vestager told reporters.
Google has 90 days to either halt such anti-competitive practices with smartphone makers and telecoms providers or seek a delay of the order while it appeals. Alphabet risks additional penalties of up to 5 per cent of average daily global revenue for non-compliance.
