A Delaware judge is set to hear arguments in a lawsuit challenging the planned $25 billion merger of cigarette makers Reynolds American Inc. and Lorillard Inc.
 
The judge was to hear arguments Friday on a motion by plaintiffs who are seeking a preliminary injunction and a motion to expedite the case.

The two companies last week announced that they would hold special shareholder meetings Jan. 28 in North Carolina, where both companies are headquartered, to vote on the merger.

The combination of the two companies would create a formidable competitor for Virginia-based market leader Altria Group, owner of Philip Morris USA.

Reynolds sells Camel, Pall Mall and Natural American Spirit cigarettes. Lorillard's brands include Newport, Maverick and Kent.

Federal regulators are conducting an antitrust review of the deal.