The Supreme Court said on Monday it would decide if the largest sex-discrimination class-action lawsuit in U.S. history against Wal-Mart Stores Inc can proceed, a case involving women workers who seek billions of dollars in damages.

The nation's highest court agreed to hear an appeal by the world's largest retailer and the largest private employer arguing the claims of as many as 1.5 million current and former female employees were too diverse to proceed as a single class-action lawsuit.

The justices decided to review a ruling by a appeals court in California that upheld the class-action certification in the lawsuit alleging discrimination against every woman employed over the past decade at the company's 3,400 U.S. stores.

The Supreme Court is expected to hear arguments in the case, which immediately became the most important business dispute before the justices this term, in March, with a ruling likely by the end of June.

The ruling could affect other class-action lawsuits. Anthony Sabino, a professor of law and business at St. John's University in New York, said the case "will test the very limits of class litigation."

Bentonville, Arkansas-based Wal-Mart said in a statement it was pleased the court granted review in the important case and it looked forward to the court's consideration of the appeal.