Iraqi armed forces launched an operation on Saturday to capture the last Islamic State-held enclave in Mosul, according to a military statement.

Iraqi forces pushed further into Mosul from the north on the second day of a new push to speed up the nearly seven-month attempt to dislodge Islamic State, commanders said on Friday.

Iraqi forces said they launched new assaults in Mosul's Old City on Monday after more than two weeks of only small advances and a high civilian death toll appeared to prompt a change in tactics.

U.S.-backed Iraqi army units on Wednesday took control of the last major road out of western Mosul that had been in Islamic State's hands, trapping the militants in a shrinking area within the city, a general and residents said.

Iraqi forces made new advances against Islamic State in eastern Mosul and fought the militants in areas near the Tigris river on Wednesday, military officials said, keeping up the momentum of a renewed offensive in the jihadists' last major Iraqi stronghold.

Iraqi forces pushed Islamic State fighters back further in Mosul on Tuesday in a renewed effort to seize the northern city and deal a decisive blow to the militant group, though progress was slow in some districts, the army said.

Iraqi Shi'ite forces fighting Islamic State west of Mosul aim to clear a large strip of land on the border with Syria to prevent the militants melting into the remote desert region and using it as a base for counter attacks, a spokesman said on Tuesday.

The offensive against Islamic State in Mosul could take two more months, and even if the group is defeated there it will still pose a threat to Iraq and the West, the commander of the U.S.-led coalition fighting against it said.

Iraqi special forces battling to clear Islamic State from eastern Mosul have killed nearly 1,000 militants but fighting has slowed as troops face a mobile enemy hidden among thousands of civilians in the city, a top commander said.

Iraqi Shiite militias were massing troops on Monday to cut remaining supply routes to Mosul, Islamic State's last major stronghold in Iraq, closing in on the road that links the Syrian and Iraqi parts of its self-declared “Caliphate”, Reuters reported.

Convoys of military vehicles loaded with Shi'ite paramilitary fighters hurtled across desert terrain in northwestern Iraq towards the Islamic State-held city of Tal Afar, chanting religious slogans and covering their faces to keep out the dust, Reuters reported.