President Barack Obama said the recapturing of Mosul dam in northern Iraq by Iraqi and Kurdish forces is a "major step forward" in the battle against Islamic State militants.

Speaking at the White House, Obama said that if the dam on the Tigris River had been breached it could have had catastrophic consequences and endangered American Embassy personnel in Baghdad.

Obama said the U.S. is urgently providing arms and assistance — along with Canada and other countries — to Iraqi security forces as well as Kurdish fighters as they seek to reverse the recent gains made by The Islamic State of Iraq and Syria (ISIS).

'In these cases, where there is an unjust aggression, I can only say that it is licit to stop the unjust aggressor.' - Pope Francis, when asked Monday about U.S. airstrikes targeting ISIS

"Going forward the United States will work with the Iraqi government, United Kingdom, Canada, France and Australia to get food and water to people in need and bring long-term relief to people who have been driven from their homes," Obama said.

The Canadian government has offered $5 million in humanitarian aid, along with two military cargo planes being used to ship weapons to Kurdish fighters.

"Canada remains committed to providing assistance to the thousands of Iraqi children, women and men, including Yazidis and Christians, who desperately need it in the face of ... repugnant terrorist attacks," said Rick Roth, a spokesman for Foreign Affairs Minister John Baird.

Regarding the Mosul Dam, Kurdish and Iraqi military spokesmen said earlier Monday the Peshmerga forces were in control of the facility and its vicinity.

ISIS captured the dam two weeks ago.

Retaking the dam could significantly boost their morale as they try to free territory overrun by ISIS in a blitz this summer. The dam and its broader complex hold great strategic value as they supply electricity and water to a large part of the country.

Army spokesman Lt. Gen. Qassim al-Moussawi said that the southern side of the complex remains contested and that fierce fighting is underway to free that area.

At least 170 bombs have been dismantled around the dam but many more remain, al-Moussawi added in a televised statement. He said that militants fled to areas near the south of the complex.

Mideast Iraq

Smoke rises during airstrikes targeting ISIS militants at the Mosul Dam. (Khalid Mohammed/Associated Press)

The U.S. launched airstrikes against ISIS more than a week ago in a bid to halt its advance across Iraq's north. The U.S. military said U.S. forces conducted nine strikes Saturday and another 16 on Sunday.

Pontiff gives qualified support

Some 1.5 million people have been displaced by fighting in Iraq since the Islamic State's rapid advance began in June. The scale of the humanitarian crisis prompted the U.N. to declare its highest level of emergency last week.

As he returned from a trip to South Korea, Pope Francis was asked if he approved of the unilateral U.S. airstrikes on the militants who have forced minority Christians and others to either convert to Islam or flee their homes.

"In these cases, where there is an unjust aggression, I can only say that it is licit to stop the unjust aggressor," Francis said. "I underscore the verb 'stop.' I'm not saying 'bomb' or 'make war,' just 'stop.' And the means that can be used to stop them must be evaluated."

But, he said, in history, such "excuses" to stop an unjust aggression have been used by world powers to justify a "war of conquest" in which an entire people have been taken over.

"One nation alone cannot judge how you stop this, how you stop an unjust aggressor," he said, apparently referring to the United States. "After World War II, the idea of the United Nations came about: It's there that you must discuss 'Is there an unjust aggression? It seems so. How should we stop it?' Just this. Nothing more."

His comments were significant because the Vatican has vehemently opposed any military intervention in recent years, with St. John Paul II actively trying to head off the Iraq war and Francis himself staging a global prayer and fast for peace when the U.S. was threatening airstrikes on Syria last year.

But the Vatican has been increasingly showing support for military intervention in Iraq, given that Christians are being directly targeted because of their faith and that Christian communities which have existed for 2,000 years have been emptied as a result of the extremists' onslaught.

Francis also said he and his advisers were considering whether he might go to northern Iraq himself to show solidarity with persecuted Christians. But he said he was holding off for now on a decision.