(Forces closing in on government buildings)
BAGHDAD, March 5 (Reuters) - U.S.-backed Iraqi forces launched on Sunday a new push toward the Islamic State-held old city centre of Mosul, on the western bank of the Tigris river, an Iraqi military spokesman said.
Iraqi forces are fighting their way toward the old centre of the city, advancing from the south and the southwest, Brigadier-General Yahya Rasool, spokesman for the joint operations command, told state-run television.
Iraqi forces captured the eastern side of Mosul in January after 100 days of fighting and launched their attack on the districts that lie west of the Tigris river on Feb. 19.
Their advance in western Mosul paused over the past 48 hours because of bad weather.
Defeating Islamic State in Mosul would crush the Iraqi wing of the caliphate declared by the group's leader, Abu Bakr al-Baghdadi, in 2014, over parts of Iraq and Syria.
Rapid Response soldiers, progressing from the south through the Dawasa and Danadan districts, are within a few hundred metres from the government buildings near the old city, a media officer with these interior ministry units told Reuters.
Taking the sites of the provincial council and governorate buildings would help Iraqi forces attack the militants in the nearby old city and would be of symbolic significance in terms of restoring state authority over Mosul. The buildings themselves are destroyed and not being used by Islamic State.
U.S.-trained Counter-Terrorism Service units meanwhile pushed through Tal al-Ruman and the Somood districts, in the southwest, Rasool said.
(Reporting by Maher Chmaytelli, editing by Louise Heavens)