Updated

The Iraqi army says it's moving units south and west of Mosul ahead of an expected push to retake the city's western half from the Islamic State group in the final, decisive battle for the city.

Brig. Walid Khalifa, the deputy commander of the Iraqi Army 9th Division, said on Tuesday that his forces have been moving into place over the past two days.

Mosul's east was declared "fully liberated" in January — over three months since the Iraqi forces' operation to retake the city had started

At the start, Iraqi forces experienced swift gains but slow and grueling urban combat followed before all of eastern Mosul was liberated. The fight for the west — a densely populated urban area — is likely going to be more difficult.