WASHINGTON (AP) — Stung by a federal judge's dismissal of its objections to AT&T's megamerger with Time Warner, the Trump Justice Department is challenging the decision with a legal appeal.

The Justice Department said in a one-sentence document Thursday it is appealing the ruling last month by U.S. District Judge Richard Leon, which blessed one of the biggest media deals ever following a landmark antitrust trial.

Leon rejected the government's argument that the phone and pay-TV giant's $81 billion takeover of the entertainment conglomerate would hurt competition, limit choices and jack up pric...