(Adds details, context of investigation)
TOKYO, Aug 6 (Reuters) - Japan's Fair Trade Commission is investigating Apple Inc over its pressure on Japanese parts makers and whether it abused its power in violation of antimonopoly rules, the Mainichi newspaper reported on Tuesday.
The investigation is the latest by the country's regulators against the tech giant after they found last year that the company may have breached antitrust rules on the way it sold its iPhones in Japan.
It also comes as Apple may face more regulatory scrutiny in the United States. Reuters reported in June that the U.S. Justice Department has jurisdiction for a potential probe of Apple as part of a broader review of whether technology giants are using their size to act in an anti-competitive manner.
Japan's FTC survey of companies showed that Apple had signed contracts forcing firms to provide free technology and know-how to its affiliates for parts manufacturing, the Mainichi said.
It also pressured some suppliers to lower components prices and prohibited them from selling parts and technology to other companies, while requiring them to shoulder the costs of any unforeseen issues, the newspaper said, citing unnamed sources.
When a company called it an infringement of intellectual property rights and demanded a revision, Apple threatened to end their business relationship, the report said.
The FTC had no immediate comment. Apple did not immediately respond to a request for comment.
Last year, the FTC investigated Apple over allegations that it unfairly pressured Yahoo Japan Corp to slow the expansion of its online games platform, which competes with Apple's App store.
The tech firm is also facing a potential U.S. investigation over allegations that App Store policies give the company too much clout over app sales and in-app purchases. (Reporting by Chris Gallagher; Additional reporting by Makiko Yamazaki and Naomi Tajitsu in Tokyo and Stephen Nellis in San Francisco; Editing by Stephen Coates)