Google LLC faces an antitrust probe in Japan after the technology giant allegedly pushed smartphone makers to use its search platform by default on their devices, the nation's fair trade watchdog said Monday.

The move by the Japan Fair Trade Commission comes after European and U.S. authorities tightened regulations on Google, which is said to hold around a 90 percent share of the global search engine market.

"We have not confirmed any illegal activities at this point," a fair trade official told a press conference, adding the commission will gather information extensively and seek inputs from outside parties, including smartphone users, as digital platformers' influence is multifaceted.

The tech giant is suspected of making the device makers feature its search application and Google Chrome browser app by default and specifying where those apps should appear on the device screens in exchange for allowing them access to the "Google Play" app store, according to the antitrust watchdog.

The Japan Fair Trade Commission holds a press conference in Tokyo on Oct. 23, 2023. (Kyodo)

It is also suspected of signing contracts with smartphone makers that would guarantee a cut of revenues earned from search-linked advertisements on condition they do not install rival firms' apps on their devices by default, among other conditions.

Google said, "We provide (users) options to customize devices in accordance with their needs," adding it will cooperate with the investigation.

The Digital Markets Act was legislated in the European Union last year to strengthen regulations on big technology companies with the aim of improving competition by facilitating the entry of new firms and providing consumers with more options.

Last month, U.S. prosecutors opened a landmark antitrust trial against Google, with the Justice Department contending that the company operates an illegal monopoly that has harmed computer and mobile device users in the United States.

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