Iraqi Prime Minister Haider al-Abadi in Baghdad, on July 23, 2015. (Clydell Kinchen/U.S. Army)

MUNICH — Iraqi forces are poised to launch a long-anticipated offensive against the Islamic State group holed up in western Mosul, one of the last bastions of fighters in a city the militant group seized control of three years ago, Iraq Prime Minister Haider al-Abadi said.

“We are now embarking on liberating the western part of the city,” he told global leaders gathered at the Munich Security Conference.

U.S.-backed forces in Iraq launched an offensive to retake Iraq’s second largest city in late 2016 after more than a year of planning. Already, the eastern section of the city has been cleared, and the assault on the larger, western section is expected to start any day.

Paratroopers of the 82nd Airborne Division have been honing the Iraqi security forces’ urban combat skills ahead of the planned offensive.

During the past year, Iraqi and Peshmerga fighters have reclaimed large swaths of territory from the Islamic State group, which overran many major population hubs with relative ease in a series of quick strike attacks in 2014 and 2015 that overwhelmed Iraqi forces. In neighboring Syria, Turkish, Kurdish and government troops also have recaptured much of he area held by the militants.

Iraq troops backed by U.S. airpower have ejected the Islamic State from cities such as Ramadi, Fallujah and Tikrit, a city where about 90 percent of displaced residents have returned, al Abadi said.

The prime minister insisted the Islamic State group is nearing defeat in Iraq.

“I am telling you a success story,” al-Abadi said.

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