WASHINGTON – Federal regulators plan to examine whether Apple Inc. is violating antitrust rules by requiring software developers to use Apple programming tools to create applications for the iPhone and iPad.

Officials at the Justice Department and the Federal Trade Commission are sorting out which agency will examine Apple’s new policy, according to a person with knowledge of the inquiry. Apple’s policy prevents developers from using outside tools such as Adobe Systems Inc.’s Flash format, which is used in many Web videos, games and interactive graphics, to design apps for Apple’s popular devices.

The person with knowledge of the inquiry, who was not authorized to speak publicly, noted that it is in a preliminary stage. The two antitrust agencies regularly scrutinize whether corporate conduct could stifle competition, and not all inquiries result in a formal investigation or action by the government.

Apple had no immediate comment Tuesday. The Federal Trade Commission and the Justice Department had no comment.

A key question facing federal regulators is whether Apple hurts competition in the mobile device market by forcing software developers to choose between designing apps that can run only on the iPhone and iPad and those that can run on rival devices such as Google Inc.’s Android phones and Research in Motion Ltd.’s BlackBerry.

Apple’s new policy has also raised concerns for Adobe, which includes Flash as part of a suite of software tools sold to professional designers and Web developers.