US regulators are launching an anti-competition probe into Google's Android operating system, the software that runs most of the world's smartphones, Bloomberg News said Friday.

The Federal Trade Commission has agreed with the US Justice Department that it will lead the investigation, Bloomberg said, citing two people familiar with the matter who were not identified.

Rival technology companies allege that Google gives priority to its own services on Android while restricting those of competitors, the report said.

The probe was at a preliminary stage and could yet end without a case against Google, Bloomberg said.

Android runs more than 80 percent of the world's smartphones, according to International Data Corp., and it usually comes bundled with Google applications including an Internet browser, email and maps.

The US Federal Trade Commission has had Google in its sights before.

In 2013, the regulator said it had no legal case against Google after an 18-month probe into allegations it had engaged in anti-competitive abuse of its dominance in Internet searches. The commission said it had secured commitments from Google to end its "most troubling practices".