The U.S. Justice Department has filed an antitrust lawsuit against Google for allegedly violating federal law by using its dominant market position to stifle competition.

The agency alleged in its long-awaited lawsuit Tuesday that Google abused its dominant market position to maintain monopolies in online search and search advertising.

Google did not immediately comment on the lawsuit, the most significant legal challenge to the U.S. technology sector in more than two decades.

Consumer advocates and legislators have long accused Google of abusing its dominant market position to suppress competition, increase profits and hurt consumers.

The suit, filed in federal court in Washington, could be the first of many other significant government antitrust actions against Silicon Valley. The Justice Department and the Federal Trade Commission also are currently investigating Apple, Amazon and Facebook.

A senior economic adviser to President Donald Trump said two years ago that the administration was considering whether Google searches should be regulated by the government.

Trump has frequently criticized Google and promoted unsubstantiated claims by conservatives that the company suppresses conservative viewpoints, meddles in U.S. elections and favors collaborating with the Chinese military over the U.S. Defense Department.

Google has captured about 90% of the world's internet search market, the result of offering a product that is preferred by billions of users daily, the company has said.

The California-based corporation has been preparing for the lawsuit and is expected to aggressively oppose any efforts to force it to spin off its services into individual businesses.

A recent House Judiciary subcommittee report concluded after a yearlong investigation into Silicon Valley's market dominance that Google has monopolized the search market. The report said Google established its dominant position through acquisition in several markets, buying about 260 companies that other businesses had developed over a 20-year span.

Google was fined $1.7 billion by the European Union in 2019 for preventing websites from using the tech giant's rivals from locating advertisers. The EU also fined Google $2.6 billion in 2017 for favoring its own online shopping venues over its rivals, and $4.9 billion in 2018 for blocking competitors from its Android operating system.