The battle to free the Iraqi city of Mosul from ISIS is imminent and will undoubtedly end in victory for the country’s forces, but it will be a fierce fight, U.S. Retired Army Gen. David Petraeus said.
Iraqi forces will soon launch a strategic offense "orders of magnitude larger than any fight that the Iraqis, with our assistance and coalition support" have taken on in the fight against ISIS in that country, Petraeus told ABC News' Martha Raddatz on "This Week."
He said ISIS will fight hard to maintain its last stronghold in Iraq, which it has controlled for more than two years.
"There will be a ring of fire. They have already lit it supposedly," said Petraeus, who commanded U.S. forces during the Iraq War and drove al-Qaeda out of that country. "There will be dug-in troops, there will tunnels. There will be suicide bombers, improvised explosive devices."