The Justice Department could sue Apple Inc as early as Wednesday over alleged electronic book price-fixing, while settling with several publishers as early as this week, two people familiar with the matter said.

The Justice Department is investigating alleged price-fixing by Apple and five major publishers: CBS Corp's Simon & Schuster Inc; HarperCollins Publishers Inc; Lagardere SCA's Hachette Book Group; Pearson and Macmillan, a unit of Verlagsgruppe Georg von Holtzbrinck GmbH.

A lawsuit against Apple, one of the parties not in negotiations over a potential settlement, could come as early as Wednesday but no final decision had been made, the people said.

Apple declined to comment. The Justice Department and the five publishers could not be reached for comment.

The Justice Department is investigating whether deals Apple cut two years ago with the quintet of major publishers - when the consumer electronics maker launched its iPad tablet computer - were done with the intent of propping up prices for digital books, sources have said.

As part of those agreements, publishers shifted to a model that allowed them to set the price of e-books and give Apple a 30 percent cut of sales, the sources have said.

Talks between the Justice Department and some publishers had been proceeding, with settlements expected as soon as this week, one of the two sources familiar with the matter said on condition of anonymity, because the discussions were not public.