Republican presidential candidate
Donald Trump has said Hillary Clinton's foreign policy plan in Syria
would trigger World War Three.
Mrs Clinton has been proposing a no-fly zone over Syria, which some say could lead to conflict with Russian jets.
The Clinton campaign accused Mr Trump of "playing to Americans' fears". Mr Trump also attacked Republicans for not uniting behind his candidacy.
"If we had party unity, we couldn't lose this election to Hillary Clinton," he told Reuters news agency at Trump National Doral golf resort in Miami, Florida.
The Republican standard-bearer struck an apocalyptic tone when criticising his Democratic rival's plan to control Syrian air space. "You're going to end up in World War Three over Syria if we listen to Hillary Clinton," Mr Trump said.