Donald Trump and his running mate Mike Pence are divided on how to solve the longstanding war in Syria.

Debate moderator Martha Raddatz of ABC News asked Trump what he would do as president "about Syria and the humanitarian crisis in Aleppo." Raddatz reminded Trump that Pence said "provocations need to be met with American strength, and if Russia continues to be involved along with the Syrian forces, the United States of America should be prepared to use military force to strike the military targets of the Assad regime" at last week's vice presidential debate.

"He and I haven't spoken, and I disagree," Trump answered. "Syria is no longer Syria. I believe we have to get ISIS. We have to worry about ISIS before we can get too much more involved."

The billionaire said both Obama and Clinton "had a chance to do something" about ISIS.

When asked by Raddatz what will happen if Aleppo falls, Trump responded, "It basically has fallen."

"You take a look at Mosul and the biggest problem I have with the stupidity of foreign policy," he said.