The charges, filed in federal court, were brought by the US Department of Justice and 11 other states. The lawsuit focuses on the billions of dollars Google pays each year to ensure its search engine is installed as the default option on browsers and devices such as mobile phones.

Officials said those deals have helped secure Google's place as the "gatekeeper" to the internet, owning or controlling the channels for about 80% of search queries in the US.

"Google has thus foreclosed competition for internet search," the lawsuit said. "General search engine competitors are denied vital distribution, scale, and product recognition - ensuring they have no real chance to challenge Google."

It added: "Google is so dominant that 'Google' is not only a noun to identify the company and the Google search engine but also a verb that means to search the internet."

The case could be the first of many in the US that challenge the dominance of big tech firms and potentially lead to their break-up.

Coming just a few weeks before the US presidential election, it has also been viewed as a move by the Trump administration to prove its willingness to challenge the influence of the sector if it gains a second term.

Officials said they had not rushed the investigation to ensure it was filed before the election.

"We're acting when the facts and the law warranted," deputy attorney general Jeffrey Rosen said, adding that the department's review of competition practices in the technology sector is continuing.