BAGHDAD: The latest reports coming in from the Iraqi army commander is that they have retaken two villages south of Mosul as the offensive to retake the area has intensified.
Iraqi forces launched an offensive on militants defending Mosul's west bank on Sunday, in what could be the most brutal fighting yet in a four-month-old operation in the city.
"Our forces are beginning the liberation of the citizens from the terror of Da'ish," Iraqi Prime Minister Haider al Abadi said in a short televised speech.
"We announce the start of a new phase in the operation. We are coming, Nineveh, to liberate the western side of Mosul," he said.
Federal police and interior ministry forces were expected to start the new phase in the offensive by moving on Mosul airport, which is on the southern edge of the city.
The militants have put up stiff resistance to defend Mosul, their last major stronghold in Iraq and the place where their leader Abu Bakr al Baghdadi proclaimed a 'caliphate' in 2014.
After shaping operations around Mosul, it took Iraq's most seasoned forces - the elite Counter-Terrorism Service (CTS) - more than two months to clear the eastern side of Mosul.
Iraq forces launch operation to cut Mosul off from Syria
After a pause in the operation launched on October 17, federal forces now face what was always billed as the toughest nut to crack: Mosul's west bank, home to the narrow streets of the Old City.
"West Mosul had the potential certainly of being more difficult, with house-to-house fighting on a larger and more bloody scale," said Patrick Skinner, from the Soufan Group intelligence consultancy.
The streets around the historical centre, which includes the mosque in which Baghdadi made his only public appearance in June 2014, will be impassable for many military vehicles and force government fighters to take on IS in perilous dismounted warfare.
Prior to the offensive that saw IS seize Mosul and much of Iraq's Sunni Arab heartland nearly three years ago, the east bank was more ethnically diverse than the west, where analysts believe the terrorists could enjoy more support.
Iraq announces start of offensive to retake Mosul
"IS resistance could be greater in this area and it will be harder, but all the more important, to completely clear the networks from Mosul after its recapture," said Emily Anagnostos, Iraq analyst at the Institute for the Study of War.
While the federal forces' attrition is said to be high, IS's had been undoubtedly higher and commanders have said the militants may no longer have the resources to defend east Mosul effectively.
"Mosul is going better than we expected, but there are serious dangers ahead," said Lise Grande, UN humanitarian coordinator in Iraq.