The NATO mission in Iraq, which consists of several hundred personnel, trains the country's security forces at the request of the Baghdad government to prevent the return of the Islamic State jihadist group.

"NATO's mission is continuing, but training activities are currently suspended," said the spokesman, Dylan White.

He also confirmed that NATO Secretary General Jens Stoltenberg had spoken by telephone with US Secretary of Defence Mark Esper "following recent developments."

A US defence official told AFP earlier Saturday that US-led forces helping Iraqi troops fight jihadists have scaled back operations.

Soleimani, the head of the Islamic Revolutionary Guards Corps' Quds Force foreign operations arm, was killed in a US drone attack in Baghdad on Friday.

The strike also killed the deputy head of Iraq's Hashed al-Shaabi, a network of mostly Shiite factions close to Iran and incorporated into the Baghdad government's security forces.

The attack shocked the Islamic republic and sparked fears of a new war in the Middle East.