US-backed Iraqi forces are set to reach the main government complex in Mosul, their next target in the battle to retake the city from Islamic State.
The site should be taken on Monday, Lieutenant Colonel Abdel Amir al-Mohammadawi told the Reuters news agency.
Meanwhile, Colonel John L Dorrian, spokesman for Operation Inherent Resolve, the American-led coalition against ISIS, told Sky News the Iraqi forces were "imposing their will on the enemy" in the city.
"They're not going to be pushed out of Mosul - they're going to surrender or they're going to be killed there," he vowed.
A senior commander said earlier Iraqi troops had been involved in the "heaviest" clashes yet with ISIS fighters in the west of the city since the start of their offensive.
Major General Haider al-Maturi of the Federal Police Commandos Division told the Associated Press the militants had dispatched at least six suicide car bombs, which were all destroyed before reaching Iraqi forces.
He said ISIS fighters are moving from house to house and deploying snipers.
Iraqi forces launched attacks against ISIS-held neighborhoods in western Mosul from three points on Sunday morning.