Three Iraqi fighters died Monday trying to defuse bombs left behind by the jihadists in Ramadi, as the toll taken by the huge mine-clearing effort there continued to rise.

The victims were three local tribal fighters killed by the explosion of improvised devices they were attempting to defuse, Anbar province governor Sohaib al-Rawi said.

He said the danger posed by unexploded bombs and booby-traps remained an obstacle to the return of Ramadi's residents.

The local government "understands the pressing need for IDPs (internally displaced persons) to return home, but we will not allow a chaotic return resulting in more casualties," he said on social media.

"We have lost more than 35 members of the security forces and sons of the tribes (tribal fighters) this year," Hamid al-Dulaimi told AFP.

"As of yesterday, we had a toll of 15 deaths in our ranks alone," said Omar Khamis al-Dulaimi, a senior leader in the tribal fighters working alongside federal forces.

Ramadi was declared liberated when Iraqi forces wrested the main government compound back from the Islamic State group late last year, but the city was completely retaken only last month.

Laying thousands of bombs and booby-trapping buildings was the backbone of IS's defence of the city last year.

Explosive ordnance disposal training has been a main focus for the US-led coalition.

"The destruction is enormous, people are still being killed by IEDs and mines that have been left by Daesh (IS)," the US envoy to the coalition, Brett McGurk, said on Saturday during a visit to Baghdad.

"We're very focused now on the counter-IED (improvised explosive device) mission," he said.

The officials in Anbar could not provide a figure for civilians killed by unexploded bombs in Ramadi over the past few weeks.

The city was virtually emptied of its population by the time the fighting culminated, and very few civilians have been able to return because of the lack of basic services and the risk of unexploded bombs.