Eradicating the Islamic State, or ISIS, from their strongholds in Iraq could take as little as three months, Iraqi Prime Minister Haider al-Abadi said Tuesday. His comments follow a continued effort by U.S. forces to rid ISIS from the northern city of Mosul, where the terror group has held power since 2014.

The prime minister’s predictions sharply contradict that of U.S. officials, who have given ISIS-elimination efforts a two-year timeline. Abadi noted the major, sweeping gains in territory the Islamic State accrued throughout 2014 and on have slowly begun to diminish, however, with forces retreating back into Mosul, where a U.S.-led coalition is currently battling to retake the region.

RTX27XVN Iraqi security forces riding in vehicles travelling to Mosul to fight against militants of Islamic State at an Iraqi army base in Camp Taji in Baghdad, Feb. 21, 2016. Photo: Reuters

"The Americans were very pessimistic" when creating their timetable to defeat ISIS, Abadi said on Tuesday. "They used to talk about a really long period but the remarkable successes achieved by our brave and heroic fighters reduced that. I foresee that in Iraq it will take three months."

If joint-U.S. and Iraqi forces are able to successfully reclaim Mosul, it would serve as the biggest blow to the Islamic State since the group became a key player in the region two years ago. That doesn’t mean the terror group, which has claimed responsibility for inspiring recent global attacks including one targeting a Christmas market in Berlin which killed 12 people and another in Pulse nightclub in Orlando, Florida, which killed 49 people celebrating gay pride month.

Abadi remains optimistic the international operation to eliminate ISIS from Iraq will be successful long before the U.S. estimate, though the Iraqi prime minister had previously said the terror group would be removed from the region entirely by the end of 2016. The Islamic State’s successful attempts in defending its hold on Mosul have slowed efforts, though the terror group has become quickly embattled in recent weeks as Iraqi forces move in on the major city.

Mosul is one of the last cities ISIS claims power over in Iraq, besides the towns of Tel Afar and Qaim, as well as Hawija and the neighboring region. Despite losing much of their territory throughout the year, international attacks inspired or carried out by the Islamic State have risen.