Apple and Google are reported to be under a formal investigation for possible antitrust issues, the result of which could see forced changes to their boards of directors.

The Federal Trade Commission has started an inquiry into whether the close ties between the boards of the two companies reduces competition under the "interlocking directorates" clause of the Clayton Antitrust Act of 1914, the New York Times reports.

Apple and Google share two directors, Eric Schmidt, chief exec at Google, and Arthur Levinson, former boss of Genentech.

The two companies are increasingly competing in similar markets with crossovers in the mobile phone market with the iPhone and Google's Android OS which, if Android-based netbooks launch, would also extend into the laptop market too.

In addition, Google's Chrome browser is a rival to Apple's Safari, Apple's iTunes and Google's YouTube occupy online space in the same arena and both companies offer photo-editing software.

So far neither Apple nor Google has offered comment on the matter. We will keep you posted.