US federal and state antitrust enforcers are preparing a lawsuit against Google which could come this year, focusing on the tech giant's dominance of online advertising, The Wall Street Journal reported Friday.

The report, citing anonymous sources, said the case may also address how Google uses its dominant search business to stifle competition.

The US Justice Department and 50 attorneys general last year said they were looking into whether Google abused its power in the online ecosystem at the expense of rivals or consumers.

By doing so, the officials revived an antitrust probe closed in Washington several years earlier while EU and other authorities press their own cases against the California-based firm.

A report says the US antitrust probe into Google could end up in the courts this year
A report says the US antitrust probe into Google could end up in the courts this year AFP / Kenzo TRIBOUILLARD

Last year, Texas Attorney General Ken Paxton, coordinating the states' effort, said an investigation was underway "to determine the facts."

Google said it was continuing discussions with authorities.

"We continue to engage with the ongoing investigations led by the Department of Justice and Attorney General Paxton, and we don't have any updates or comments on speculation," the company said in an email.

"Our focus is firmly on providing services that help consumers, support thousands of businesses, and enable increased choice and competition."

Authorities have also begun looking at Facebook and other online platforms on issues of market dominance.

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