The deputy commander of the U.S.-led coalition working to defeat the Islamic State group said Monday "the final liberation of Mosul is drawing ever closer."
British Major General Rupert Jones said during a briefing that Iraqi forces are going block by block to clear the final militants from Mosul, a city Islamic State seized three years ago.
Jones also said the fall of the group's de facto capital in Raqqa, Syria "is just a matter of time," but cautioned that battle will not be quick or easy.
"Daesh are fighting for their lives, so their ability to plan and direct attacks is significantly degraded," Jones said, using an Arabic acronym for the militant group.
Iraqi troops backed by coalition airstrikes and ground support pushed deeper into Mosul's Old City on Sunday, with one Iraqi commander saying 65 to 70 percent of the city had been liberated.
Lieutenant Colonel Salam al-Obeidi estimated there were only "a few hundred" Islamic State fighters left in Mosul, and that there remained less than one square kilometer to retake from the militants.
Another commander, Staff Lieutenant-General Abdulwahab al-Saadim, predicted, "We will finish the operation within a few days. The end is going to be very soon, it will take days." Iraqi troops have led the fight to retake Mosul, held by the militants since 2014, but a U.S.-led international coalition has provided air and ground support.
Eight month battle
Much of the Old City has been devastated in eight months of fighting, including the landmark 850-year-old Grand al-Nuri mosque and its leaning 45-meter minaret that jihadists blew up four days ago.
With the Iraqi advance, some in Mosul celebrated the Muslim Eid al-Fitr holiday marking the end of the fasting month of Ramadan, with children playing in squares on the eastern side of the city that had been liberated months ago.
In a statement, Iraqi Prime Minister Haider al-Abadi said, "As our heroic forces are closer to declaring final victory over the Daesh (Islamic State) gangs, I offer my most sincere congratulations for Eid al-Fitr."
Even with the possibility of an imminent Iraqi takeover of Mosul, one U.S. analyst voiced concerns that Baghdad is not prepared to assume governmental control of the city.
Michael O'Hanlon, director of foreign policy research at Brookings Institution, a Washington think tank, told Alhurra, the U.S.-owned Arabic-language satellite TV network, that he is worried "about the potential of another extremist Sunni group emerging. Defeating one extremist group doesn’t stop the surge."
O'Hanlon said that after the liberation of Mosul, "governance must be preserved and all groups must have access to governance…. Otherwise Mosul can become a place where extremists can re-emerge.
WATCH: The Brookings Institution's Michael O'Hanlon on the importance of good governance after Mosul falls
"From what I hear, there is no particular concept on how to govern Mosul that’s competent and inclusive," O'Hanlon said. "It is not enough to have a couple of Sunnis in the government. People have to be governing, appointing jobs, building the police force. We’re going to have to manage frustration and grievances and the way to do that is to have an inclusive government."