The U.S Justice Department has launched a preliminary inquiry into the activities of an industry group led by Sony Corp., Matsushita Electric Industrial and Philips Electronics NV over a new format for DVDs, according to a published report Monday.

The inquiry comes as companies are competing to establish the Blu-Ray DVD format for playing movies in high-definition video, which requires far more storage space than the standard movies on today's discs, the Wall Street Journal reported.

Citing people familiar with the matter, the paper said the Justice Department is looking into the Blu-ray group, which was founded by Sony, Matsushita, Philips and seven other major electronics companies. The group is promoting the Blu-ray disc, a format that can store about six times as much data as a conventional DVD, it said.

According to the paper, a person close to the DVD Forum, an official standards-setting body for DVDs that includes hardware and software companies, said the Justice Department is looking into whether the group's members potentially acted to impede the forum's technical progress.

Neither the companies nor the department could not immediately be reached for comment.