Judge Victor Marrero of U.S. District Court for the Southern District of New York set the hearing for June 21, in response to a request for an expedited hearing.
Ten states, led by New York and California, filed a lawsuit on Tuesday aimed at stopping the merger of the No. 3 and No. 4 national wireless companies, saying that the deal would cost Sprint and T-Mobile subscribers more than $4.5 billion annually.
The Federal Communications Commission has agreed in principle to approve the deal while the U.S. Justice Department is believed to be nearing a final decision.
The companies have offered to sell the Boost brand currently owned by Sprint to reduce the combined company's market share in the prepaid business. They have also indicated they were considering divesting wireless spectrum.
T-Mobile indicated in a filing on Thursday that its attorneys will include George Cary and David Gelfand, who oversaw litigation at the Justice Department's Antitrust Division during the Obama administration when there were at least three major merger challenges.
Sprint has filed that its attorneys will include Karen Hoffman Lent and Steven Sunshine of Skadden, Arps, Slate, Meagher & Flom, who have handled some of the biggest antitrust cases in the past 10 years.