The parent company of T-Mobile, Deutsche Telekom, said it was gearing up for a court battle with the Federal Communications Commission, which filed a lawsuit to block the merger on antitrust concerns, The New York Times reported Friday.
But the two companies said they had canceled the FCC application.
In addition, the companies said AT&T was expecting to take a $4 billion charge that would be assessed if the $39 billion deal is not completed.
As the FCC prepared to send the case to an administrative law judge, at least one analyst said the deal was all but dead.
"The fat lady hasn't started singing yet, but she's holding the mike, and the band is about to play," said industry analyst Sanford Bernstein.
He said pulling the application to the FCC "is a tacit acknowledgment by AT&T that this story is all but over."