Humanitarian workers were clamoring on Sunday for resources to cope with the tens of thousands of displaced Iraqis who fled Fallujah as the government pushed to wrest the city from the hands of "Islamic State" (IS) militants.

The UN refugee agency, UNHCR, estimated that 84,000 people have had to flee the city since the army campaign to retake it began nearly a month ago.

"Agencies are scrambling to respond to the rapidly evolving situation, and we are bracing ourselves for another large exodus in the next few days as we estimate that thousands more people remain trapped in Fallujah," the UNHCR reported.

Refugees stranded in summer heat

Internally displaced people were suffering not only from hunger and trauma, but the scorching summer heat is also especially dangerous for those without access to shelter. Temperatures in Baghdad on Sunday were around 44 degrees Celsius (111 Fahrenheit).

An Iraqi aid worker employed at a nearby refugee camp said their resources were woefully inadequate.

"We secured tents for some of them, but the rest, including women and children, are sleeping on the ground under the sun," he said. "Their situation is a tragedy."

Prime Minister Haider al-Abadi vowed to support the refugees as the government fights to root out the remaining jihadis holed up in the northern part of Fallujah.

On Friday evening Abadi announced that the city had been "brought back to the fold" despite the leftover militants, sniper fire, car bombs and booby traps.

The government announced its intention to turn the fight towards a renewed siege of Mosul, Iraq's second-largest city which has spent two years under IS occupation.

es/jm (AP, AFP)