Iraqi forces backed by jets and helicopters battled jihadists inside west Mosul Saturday, February 25 but still faced a tough and potentially protracted battle to retake the Islamic State group's bastion, AFP reports.

Almost a week into a major push on the city's west bank, they were gaining significant ground, taking on IS on several fronts in one of the most intense phases of the four-month-old operation to retake Mosul.

Elite forces from the interior ministry's Rapid Response units that retook Mosul airport pressed north towards the centre of the city but their advance was expected to slow as they moved in deeper.

"Right now we're heading towards the Mosul governorate building, we're now about one kilometre from the fourth bridge," referring to the city's southernmost bridge across the Tigris River, Lieutenant Colonel Abdulamir al-Mohammadawi told AFP on the front line in west Mosul.

"We're heading towards the centre and also the Turkish consulate, which we're about 500 metres from," he said, as attack helicopters fired rockets on targets in the Jawsaq neighbourhood.

As they pushed deeper from the outer edges of the city into more densely-populated areas, resistance appeared to get stiffer.

"Daesh is using houses full of residents as human shields," Mohammadawi said, as tanks and troops rained fire on suspected IS snipers.

Moments later, Rapid Response fighters helped two wounded comrades back to the rear for treatment. They were moaning in pain and one was wearing a tourniquet above his knee after being shot in the leg by a sniper.

In areas now rid of the jihadists, residents told of their lives under IS rule and celebrated their recovered freedom.

"They made us wear short trousers and beards, cigarettes were forbidden. The women had to cover even their eyes, it was forbidden even for their eyes to appear," said 20-year-old Othman Raad as he sat on the steps of his home in Jawsaq.

"Now we feel relaxed, our children are safe, we are safe," he said, even as the fighting raged blocks away.

Iraqi forces launched a fresh push from the south on February 19, nearly a month after the eastern side of Mosul was declared "fully liberated".

The west bank of Mosul is where Abu Bakr al-Baghdadi made his only public appearance as IS leader in July 2014 and proclaimed a "caliphate" straddling Iraq and Syria.

The group once controlled about a third of Iraq but after more than two years of a government fightback supported by powerful allies such as the United States and Iran, the west bank of Mosul is the last major jihadist bastion in Iraq.

Iraqi forces made quick gains in recent days, blitzing through some of the last open areas south of the city and retaking the airport, whose runway is now a field of rubble.