US-backed Iraqi security forces battling Daesh faced tough resistance from snipers and mortar rounds on Monday as they tried to advance on Mosul's Old City and the Iron Bridge across the Tigris River.
Iraqi security forces said at the weekend they had entered the Bab al Tob area of the Old City, where fighting is expected to be toughest because of its narrow alleyways, where armoured vehicles cannot pass.
But the advance in western Mosul stalled on Monday because of poor weather conditions.
"Due to the bad rainy weather, operations have been halted for now. We are facing stiff resistance from Daesh fighters with snipers and mortars," an Iraqi official said.
Iraqi forces are moving to seal off the entire Old City from the rest of Mosul.
"We [are] moving on the old bridge... and then we will free that area and hopefully in a few days we'll liberate the west side of Mosul," a captain from the security forces said.
If Iraqi forces recapture Iron Bridge, they will control three of the five bridges spanning the Tigris River between eastern and western Mosul. The southernmost two bridges have already been retaken by Iraqi forces. Taking Iron Bridge would effectively trap the remaining Daesh fighters inside the Old City.
Humanitarian catastrophe threatens
As many as 600,000 civilians are thought to still be in the Old City along with the militants.
The International Organisation for Migration said more than 200,000 people have been displaced by fighting in Iraq's second largest city since the start of the Mosul offensive in October.
More than 65,000 of them fled their homes over the past two weeks, the organisation said.
Surge in civilian casualties
A prominent Sunni business leader from Anbar province has warned the US-backed government coalition that speeding up the campaign to drive Daesh out of Mosul has led to a surge in civilian casualties that threatens to undermine efforts to crush the militants.
"There were heavy casualties due to speeding up of military operations and we see this as a big mistake and residents who we are in touch with have much more fear than in the past of the ongoing military operations," Khamis Khanjar said in an interview in Amman, Jordan.
Khanjar said at least 3,500 civilians have been killed since the operation to liberate the western part of the city began last month.
"We hope the US-led coalition doesn't hurry up in this way without taking into consideration the human lives," said Khanjar, founder of the Office of the Sunni-Arab Representative for Iraq.
Iraqi forces took full control of eastern Mosul at the end of January, 100 days after the US-backed campaign to dislodge Daesh militants from the city began.