BAGHDAD: Iraq’s Sunni province of Anbar is key to launching the long-awaited operation to retake the city of Mosul from ISIS militants, the country’s defense minister said Wednesday.

Khaled al-Obeidi’s remarks reflected the challenges Iraqi forces, backed by U.S.-led coalition airstrikes, face as they try to claw back territory captured by ISIS. 

They also indicate that the operation to take back Mosul, Iraq’s second-largest city, may come later than expected.

At the moment, Iranian-backed Iraqi soldiers and allied Shiite militias are fighting to retake ISIS-held city of Tikrit, Saddam Hussein’s hometown – an offensive that is taking place without U.S. airstrikes.

Obeidi told reporters Wednesday that before Iraqi forces can undertake the battle for Mosul, they must “secure” Anbar so that it cannot serve as a staging ground for militant counterattacks.

Anbar, west of Baghdad, was the first province to fall under the control of ISIS during the group’s blitz last year. The province shares a long border which Syria, which has enabled the militants to move fighters and weapons between the two countries virtually unpoliced.

“We must secure Anbar and we are now focused on securing Anbar,” Obeidi said. He singled out the town of Hit, in Anbar, saying it is an obvious place from where ISIS can strike back.

Tikrit is viewed by Iraqi forces as key to opening a strategic corridor that leads to Mosul from one direction. U.S. officials had said that there would likely be a spring offensive to reclaim Mosul, but Iraqi officials have backed away from setting a timeline.

Also Wednesday, a leading international rights group accused Iraq’s Shiite militias fighting alongside government forces of carrying out the “deliberate destruction of civilian property” after the town of Amirli, northeast of Baghdad, and the surrounding area was recaptured from ISIS last year.

Human Rights Watch, in a report focusing on the Shiite militias’ role in freeing Amirli, cited evidence of militiamen looting the property of Sunni civilians who had fled the fighting, burning their homes and businesses, and destroying at least two villages.

“Iraq clearly faces serious threats in its conflict with ISIS, but the abuses committed by forces fighting ISIS are so rampant and egregious that they are threatening Iraq long-term,” said Joe Stork, the deputy Middle East and North Africa director at HRW.

“Iraqis are caught between the horrors ISIS commits and abusive behavior by militias, and ordinary Iraqis are paying the price,” he added.

The spokesman for Prime Minister Haider al-Abadi’s office said the Iraqi government has “zero tolerance for any human rights violations.”

In response to the report by the New York-based watchdog, Rafid Jabouri said that “if anything needs to be investigated, it will be.”

Elsewhere, a rare bombing in southern Iraq killed at least three people and wounded four others near Umm Qasr port Wednesday, police and a hospital source said.

The bomb exploded at about 9 a.m. in an area where trucks wait to enter the port near the city of Basra to pick up goods, hitting a vehicle belonging to a transport company.

South Iraq is usually spared the deadly violence that has plagued Iraq.

Separately, Canada’s prime minister said he would ask parliament next week to extend and broaden a six-month mission fighting ISIS in Iraq due to wrap up next month.

With a Conservative majority in the House, the government’s motion is assured to pass.

“Next week, it is the government’s plan to move forward with a request to Parliament for extension and expansion of the mission,” Prime Minister Stephen Harper said.

“And I will obviously give more details when we do that,” he added.

The military mission started in November with Canadian warplanes joining U.S.-led airstrikes on ISIS.

Canada also deployed 69 special forces troops to train Kurds in northern Iraq.

A clash mid-January in which the Canadians came under mortar and machine-gun fire while training Iraqi troops near the front lines, as well as a recent friendly fire death of a Canadian soldier, however, have underscored political divisions in Ottawa over the mission.

The opposition has accused Harper of lying when he outlined mission parameters to parliament in October that were supposed to limit ground forces to a non-combat role.

But Harper has been unapologetic – backed by a majority of Canadians who support the mission in the aftermath of two attacks in Ottawa and rural Quebec the same month.