In his first visit to nearby Kirkuk province since becoming prime minister, Abadi met with provincial and military leaders and inspected military units.
Speaking to security officials in the northern Iraqi province, Abadi said he was preparing for a large-scale operation to take back multiple cities now controlled by the terrorist group.
"We are fighting to liberate our people, and by the determination of our heroic force we will liberate the people of Hawija, Riyadh and Rashad from the terrorist gangs," Abadi said.
The Iraqi military won't be alone in this fight. The Kurdish Peshmerga, along with the Shiite paramilitary forces -- known as the Popular Mobilization Units (PMUs) -- will join the anti-ISIS coalition, according to an official statement from the PMU.
Chief among those battles will be a fight for control of Hawija, located about 100 miles south of Mosul and the last major ISIS stronghold in the oil-rich Kirkuk province. Hawija has been under ISIS control since 2014. About 1,200 ISIS fighters are inside the city and surrounding villages, according to Iraqi security sources.
The battle is expected to take place in the air and on the ground, and has already been bolstered by more than a year of airstrikes against ISIS targets by Iraq and coalition forces.
Having nearly cleared ISIS from Anbar and Salaheddin provinces, the retaking of Hawija would be a significant development for the anti-ISIS coalition, especially with its sights set on Mosul, the largest Iraqi city under the terrorist group's control.
Capturing Hawija would help eliminate, or at least lessen, any possible threat to Iraqi and Peshmerga forces who would have their backs to the city during the battle for Mosul.
Baghdad and Ankara exchange barbs
But such displays of unity have been beset by regional rivalries. Chief among them is the spat between Turkey and Iraq. At the center of this controversy has been Baghdad's objections to Ankara's military presence in the country's north.
Turkish forces have been training troops in Bashiqa -- a town in Mosul province -- without the permission of Baghdad, but with the authorization of the Kurdistan Regional Government
"The recent spat between Ankara and Baghdad should be seen in the context of broader ethnic-religious fault lines. Ever since the fall of Saddam Hussein, Turkey has viewed Baghdad suspiciously close to Tehran and has become closer to the Kurdistan Regional Government," Joshua Walker, fellow at the German Marshall Fund, told CNN.
Turkey, now hosting 2.5 million Syrian immigrants, also fears that more people will cross the border if the anti-ISIS operation is unsuccessful or stirs sectarian turmoil.
Turkish President Recep Tayyip Erdogan is adamant his country will contribute to the fight against ISIS inside Iraq, suggesting it will play a role with or without Iraq's invitation.
"We are determined to take our place with the coalition forces in Iraq, for Iraq's unity and solidarity. If coalition forces do not want Turkey, our plan B will be put into action. If that doesn't happen, our plan C will be put into action," Erdogan said Friday at a public event in Konya in southern Turkey.
He did not specify what a plan B or C would entail.
Abadi, however, struck a defiant tone in defending Iraq's sovereignty.
"Iraq wants to live with all the neighboring countries in peace. We reject any interference in our internal affairs, and Iraq's sovereignty and the unity of its territory is fundamental for us," he said during his visit to Kirkuk.
In a brazen display of the kind of warfare to come, ISIS has resorted to setting oil wells ablaze in Al-Qayyara -- a city located between Mosul and Hawija -- before being pushed out. In Mosul, ISIS has begun to dig trenches around the eastern perimeter of the city.
Concerned about the dire humanitarian situation, the International Rescue Committee said up to a 100,000 people could be without shelter in the first few weeks of the military operation to retake Mosul.
Although ISIS seeks to create an Islamic caliphate through war, it has lost considerable territory in the last two years.
Since April 2015, Iraqi forces have retaken control of Tikrit, Ramadi and Falluja.