Patriot missile launchers and two other short-range systems are now in place at al-Asad Air Base, where Iran carried out a massive ballistic missile attack against U.S. and coalition troops in January, and at the military base in Irbil, said officials.

The K1 Air Base is the third site coalition forces have left this month, in line with U.S. plans to consolidate its troops in two locations in Iraq.

The U.S.-led coalition said at least 25 107mm rockets struck Camp Taji, north of Baghdad, just before 11 a.m. Some struck the area where coalition forces are based, while others fell on air defence units, the Iraqi military statement said.

U.S. Defense Secretary Mark Esper, in a Pentagon statement detailing the strikes, cautioned that the United States was prepared to respond again, if needed.

Officials did not say what group they believe launched the rocket attack, but Kataib Hezbollah or another Iranian-backed Shia militia group is likely.

The attack came just before 3:30 a.m. local time, according to Col. Myles B. Caggins III, a spokesman for the U.S. military operation in Iraq. He only said the rockets hit the base hosting U.S. and other coalition forces.

The minister's comments followed news the Iraqi government had agreed to let NATO's Canada-led training mission continue, weeks after the country's parliament passed a resolution demanding all foreign troops leave.

It was a rare moment of respite during which residents took selfies and children played in parks, lobbing snowballs before the fluffy flakes disappeared and the white cover dissolved into grey puddles.

Trudeau delivered that message two hours after touching down for a whirlwind visit to a base where many Canadian troops had to relocate about a month ago from Iraq.

Some of those affected are close relatives of refugees who are already in the U.S., while others are from 11 countries, including Egypt, Iran and Somalia, that Trump singled out, citing security reasons.