AMMAN, Jordan -- A major aid agency said Wednesday that 27.8 million people around the world were internally displaced by conflicts and natural disasters last year, calling it a global crisis.

That's as many as the combined populations of New York City, London, Paris and Cairo -- or an average of 66,000 people displaced every day in 2015.

said that 8.6 million of last year's internally displaced were uprooted by conflict, more than half of them in Syria, Yemen and Iraq.

The group says Yemen alone accounted for one quarter of conflict-related displacement worldwide last year, with 2.2 million people uprooted, or 20 times more than in 2014.

The impoverished Arabian Peninsula country, which is gripped by a war pitting Yemen's Shiite rebels known as Houthis and their allies against forces loyal to the internationally backed government, which is being aided by a Saudi-led coalition and its airstrikes' campaign targeting the rebels.

Yemen was followed by Syria with 1.3 million displaced and Iraq with 1.1 million, the report said.

The group's Middle East director, Carsten Hansen, said that while the world's attention was focused on Middle Eastern refugees, or those who fled their homelands, millions were displaced internally in the region.

"While richer, stable countries have been scheming to keep asylum seekers out of their borders and deny them protection, millions remain trapped in their own countries with death ... just around the corner," he said.

The total of those internally displaced by conflict in the world now stands at 40.8 million, including the newly displaced 8.6 million last year.

"This is the highest number ever recorded, and twice the number of refugees worldwide," said Jan Egeland, the head of the NRC.