Judge Araceli Martínez-Olguín’s Monday ruling puts the deal on hold for two weeks while she considers a broader antitrust legal challenge brought by a coalition of 12 state attorneys general, led by California AG Rob Bonta.

A federal court issued a 14-day restraining order, siding with states that argue the massive media merger violates antitrust laws.

The Democratic attorneys general allege that Paramount's purchase of Warner Bros. would reduce competition, hurting filmgoers along with TV and news consumers and especially those who create entertain...