Kurdish security forces rescued a 16-year-old Swedish girl, Marlin Stivani Nivarlain, from Islamic State-controlled territory near Mosul in northern Iraq on February 17, according to a statement from the Kurdistan Regional Security Council. Nivarlain was interviewed by Kurdistan24 after her rescue, and told them she was misled by her boyfriend, an Islamic State supporter, into traveling to Mosul in May 2015, without a proper understanding of what IS was. She described her journey across Europe and through Syria, and poor conditions in Mosul. She thanked the Kurdistan Regional Security Council for rescuing her. NOTE: To use this video, you must provide credit to Kurdistan24, and link to their story. Credit: Kurdistan24

THE long-anticipated battle to wrest the northern Iraqi city of Mosul from the Islamic State is imminent. The liberation of the second biggest city in Iraq would prove the most defining and morale-boosting moment in the entire war to date, and give new courage that the days of ISIL are numbered.

Recent imagery from the outskirts of Mosul, a city that once held two and a half million people but has dwindled to one million after ISIL seized it in June 2014, suggests things have gone very quiet, with barely a car seen moving.

It is thought that Mosul’s estimated 10,000-strong ISIL force has drawn into the centre of the city, along with the remaining civilian population, as it prepares for a showdown. The population is a mix of ISIL supporters and those who are trapped and will be used as human shields.

Last week, Iraqi aircraft flew over the city and dropped hundreds of thousands of leaflets, advising people that help was finally coming. They told the population that Iraqi forces had been victorious late last year in the battle for Ramadi, east of Baghdad, and advised them to be ready for “the biggest battle”.

FORCES GATHER

This week, the US-led fighters attacked chemical sites near Mosul supposedly used to produce mustard gas. It comes a week after the Pentagon announced it was using cyber interference to block telecommunications within Mosul as it prepares to assist Iraq in retaking Mosul at an undisclosed date, in the immediate future.

Iraqi news outlets have been reporting that ISIL is currently sieving through the local population, arresting hundreds who refuse to join them in the defence of the city.

When News Corp recently visited the Australian forces In Taji, just north of Baghdad, they were training a battalion of Iraqi soldiers who were from Mosul and were being readied for the liberation.

Since then, the Iraqi army has been gathering in the Makhmour province, just south of Mosul, in anticipation of the fight.

JOCKEYING FOR POSITION

Kurdish forces have Mosul surrounded and are holding the insurgents in place, and have reportedly in recent weeks had “dozens” of ISIL fighters surrender to them, fearing they will die in Mosul.

Several weeks ago, Kurdish-led forces overran and recaptured the ISIL-held city of Shaddadi, in eastern Syria, the main town along the supply route that had linked Mosul to ISIL’s headquarters in the Syrian city of Raqqa.

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Mosul is now isolated and everything appears in place for an invasion, though there is politics on who will lead the assault. While the Kurdish forces that operate out of their autonomous province in northern Iraq have done most of the fighting so far, the Iraqi government is anxious that its own soldiers will be first into Mosul.

That is partly because the oil-rich city, which is outside of formally agreed Kurdish lands, is nonetheless seen by some Kurds as part of their realm. The Iraqis don’t want the Kurds to take Mosul and then claim it as their own.

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The Wall Street Journal reported this week that Iranian-backed Shia militia are also demanding to join the fight, after they were denied a place in the battle for Ramadi. Mosul is majority Sunni and there are concerns involving Shia militia will cause infighting, as well as increasing Iranian influence in the region.

PRESSURE MOUNTS

There is added urgency to move on Mosul.

The enormous Mosul Dam sits some 50km north of the city. Its walls are said to be fractured and could breach at any time. On Thursday, the US Ambassador to the UN, Samantha Power, posted on Twitter: “Just left chilling briefing on Mosul dam in Iraq; failure could leave Mosul city under 15m of water in only hours.”

Mosul Dam sits on the Tigris River, which runs through Mosul. It feeds all the way down to Baghdad. Ms Power tweeted that if the dam collapsed, the “entire pop of Baghdad wld face choice to flee or risk being stranded by flood”.

Just left chilling briefing on Mosul dam in Iraq; failure could leave Mosul City under 15m of water in only hours. pic.twitter.com/FqJuC4SiVy — Samantha Power (@AmbassadorPower) March 9, 2016

Mosul dam failure wld be catastrophic—entire pop of Baghdad wld face choice to flee or risk being stranded by flood pic.twitter.com/O5u2ZBUojz — Samantha Power (@AmbassadorPower) March 9, 2016

An Italian firm is now desperately trying to strengthen the dam, but Coalition forces must be worried that ISIL could in a last act of spite attempt to blow the dam.

Victory in Mosul will not the mean the end for ISIL, who are now spread out across northern Syria and eastern Iraq. But it will be a hugely damaging loss that no amount of their propaganda can correct. And it will send the surest signal yet that the Islamic State has a use-by date.