An Iraqi commander expects to dislodge Islamic State from Mosul in May despite resistance from militants in the densely populated Old City district, Reuters reported.
The battle should be completed "in a maximum of three weeks", the army's chief of staff, Lieutenant General Othman al-Ghanmi, was quoted as saying by state-run newspaper al-Sabah on Sunday.
A U.S.-led international coalition is providing air and ground support for the offensive in Mosul, the largest city in northern Iraq, which fell to hardline Sunni Muslim fighters in June 2014.
Islamic State has lost most of the city since the offensive began in October and is now surrounded in the northwestern districts, including the historic Old City center.
The United Nations believes up to half a million people remain in the area, 400,000 of whom are in the Old City with little food, water and medicine.
The militants have dug in among the civilians, often launching deadly counter-attacks to repel forces closing in on the Old City's Grand al-Nuri Mosque, from where Islamic State leader Abu Bakr al-Baghdadi declared a caliphate over parts of Iraq and Syria.
The hardline group persecuted non-Sunni communities and inflicted harsh punishments on Sunnis who do not abide by its extreme interpretation of Islam.