ISIS supply lines to Mosul completely cut off by coalition forces

Mosul, the Islamic State group’s last major stronghold city in Iraq, is completely cut off, Iraqi officials announced on Wednesday. The news came as Iranian-backed militias known as the The Popular Mobilization Units said they had shut down a key route west of Mosul that had served as the terror group’s last remaining supply line between the northern Iraqi city and its central hub in Raqqa, Syria.

The stronghold city is now surrounded by coalition forces, according to Iraqi Joint Operations Command, meaning IS will be less able to move weapons or supplies into the city. Kurdish Peshmerga forces have led the effort from the north and south before connecting with the Iranian-backed militias in the west, according to the AFP. The Iraqi Army and its special forces recently entered the city from the east and are the only military forces allowed to enter the actual city.

Mosul is one of the terror group’s most strategically important locations, serving as a critical supply and trade hub between the group’s quasi capital in Raqqa, Syria, and an early cash flow generator because of its its proximity to some of Iraq’s major oil fields.

Wednesday’s news marks the most significant advancement in weeks for the U.S.-backed Iraqi-coalition’s offensive that began on October 17, but it is far from the end.

The Iraqi Army and special forces are now engaged in slow and bloody urban warfare as they close in on the city’s center. Their advance will likely grind on for some time as they contend with IS tactics that have included riddling the city with booby-traps, setting off suicide car bombs, stationing snipers on rooftops and using civilians as human shields.

Wednesday’s news is a major blow to the besieged terror group, however, and will likely pose severe challenges in its months-long fight to hold on to the city, as the flow of militants and supplies will likely dwindle to a drip.

Though Wednesday’s advancement marks the latest achievement in the U.S.-backed coalition’s offensive, it once again raises questions of how the coalition’s make-up — a mix of Shia, Kurdish and Christian paramilitary groups along with federal forces — will factor into redrawn territory decisions and the safe passage of civilians once the city falls.