Updated

France's defense minister says the battle for the Iraqi city of Mosul could last months but is "essential" to preventing new Islamic State attacks.

Defense Minister Jean-Yves Le Drian told reporters Tuesday that IS extremists plotted the group's recent attacks against France from their strongholds of Mosul and the Syrian city of Raqqa, "and they are fomenting other possible attacks. So we need to strike at the heart."

He continued, "It's not a Blitzkrieg . It's a city of a million and a half inhabitants, so this is an affair that will last a long time."

French warplanes and artillery are active as part of the U.S.-led coalition supporting the Iraqi military campaign to take back Mosul. French airstrikes Sunday destroyed a factory making improvised explosive devices.