Iraqi troops will begin a “major ground offensive” in coming weeks to regain control of territories captured by the Islamic State group, General John Allen, the U.S. coordinator for the anti-ISIS coalition, said, in an interview to Jordan’s Petra news agency on Sunday.

“In the weeks ahead, when the Iraqi forces begin the ground campaign to take back Iraq, the coalition will provide major firepower associated with that,” Allen reportedly said, adding that the U.S. is “doing all it can” to aid the Iraqi army.

Since June last year, ISIS has seized vast swathes of territory in Iraq, including the cities of Mosul and Tikrit. In November last year, the Iraqi army had reportedly retaken the Baiji oil refinery, the biggest in Iraq, located about 130 miles north of Baghdad. However, fierce fighting has continued in the region and nearly 150 people were killed during the most recent clashes in the town on Sunday, according to media reports.

Allen also said, in the interview, that the anti-ISIS offensive in Syria would take much longer as the U.S. lacked a coalition partner in the country. “We have a partner at all levels in Iraq but we don't have a similar partner in Syria. So the work that must be done by the coalition in Syria is going to take longer,” he reportedly said.

Meanwhile, Jordan announced on Sunday that it had destroyed 20 percent of ISIS’ military capabilities so far, according to media reports.

“We achieved what we aimed for. We destroyed logistics centers, arms depots and targeted hideouts of their fighters,” General Mansour al-Jbour, head of the Jordanian air force, said on Sunday, adding that Jordanian warplanes had carried out 56 airstrikes on ISIS targets in Syria since Thursday, according to media reports.

“We are determined to wipe them from the face of the Earth,” al-Jbour reportedly said.

Jordan has stepped up its military offensive against ISIS after the group released a video last week showing Jordanian pilot Muath al-Kaseasbeh being burned alive in a cage. Following the release of the gruesome video, the Jordanian government vowed a “relentless war” against the militant group.