UBS, the world's largest banker to the rich, agreed last week to pay a $780 million fine and disclose the identity of about 300 of its U.S. clients to avert criminal charges.
But the Swiss bank is still facing a civil case in which U.S. authorities are seeking access to the names of another 52,000 clients.
On Monday, a U.S. judge gave the bank until April 30 to oppose the efforts and to argue it deserved the legal equivalent of a trial, the New York Times reported.
The judge said in a public conference call with UBS lawyers and Justice Department officials that any such mini-trial would take place on July 13, the newspaper reported.
UBS was not immediately available for comment.
UBS said last week it could go out of business if it complied with an order to reveal the names, saying the U.S. case would force it to violate Swiss criminal law by turning over information protected by Swiss financial privacy laws.
(Reporting by Emma Thomasson; Editing by Mike Nesbit)