The US-led coalition said it carried out an air strike Tuesday that destroyed a bridge over the Tigris river in central Mosul to stop jihadists from rotating their forces in the Iraqi city
The strike leaves Mosul's oldest bridge, which was British-built, as the only one still standing out of five in the centre of the city, according to residents.
"The reason for that is Daesh (IS) were using those as their lines of communications to re-supply their forces on the eastern side of the city and reinforce their forces, essentially rotating their forces," a coalition spokesman said.
"So were not going to let that happen," Colonel John Dorrian told AFP.
The fighting inside the city so far has focused on eastern neighbourhoods, which elite counter-terrorism and army forces entered earlier this month.
The Islamic State group has offered fierce resistance to defend its last remaining bastion in Iraq, the city where its leader Abu Bakr al-Baghdadi proclaimed a caliphate in June 2014.
The eastern bank of the Tigris was expected to offer less resistance when tens of thousands of Iraqi forces launched a huge offensive on Mosul on October 17.
Most of the jihadists' traditional bastions are on the western side of Mosul, as is the old city whose narrow streets will be hard to penetrate for the government forces' armoured vehicles.