A Syrian refugee man (obscured) moves boxes of goods at his shop in Zaatari refugee camp near the border with Syria, in Mafraq, Jordan October 15, 2016. (Photo by Ammar Awad/Reuters)

Rohingya refugee sisters Nur Kaida (R) and Ruhana hug each other at their shelter at the Palongkhali refugee camp near Cox's Bazar, Bangladesh December 21, 2017. (Photo by Marko Djurica/Reuters)

This photo taken on April 7, 2018 shows Rohingya refugee attending a demonstration of elephant resistance arranged by the UNHCR and IUCN at the Kutupalong refugee camp in Ukhia, Bangladesh. The purpose of the training day is sobering – a dozen Rohingya have been killed by wild elephants whose habitat has been consumed by Kutupalong refugee camp. (Photo by Munir Uz Zaman/AFP Photo)

Syrian refugee girl Nur El-Huda, 9, shows a drawing of her home in Syria, in her classroom in Yayladagi refugee camp in Hatay province near the Turkish-Syrian border, Turkey, December 16, 2015. Syria's conflict has left hundreds of thousands dead, pushed millions more into exile, and had a profound effect on children who lost their homes or got caught up in the bloodletting. The drawings of young refugees living in Turkey show their memories of home and hopes for its future. The pictures also point to the mental scars borne by 2.3 million Syrian refugees living in Turkey, more than half of them children. (Photo by Umit Bektas/Reuters)

The Syrian refugee folklore troupe Abu Rustom perform at a wedding show at Zaatari refugee camp in the Jordanian city of Mafraq, near the border with Syria February 20, 2017. The Syrian troupe is trying to keep its country's traditions alive by holding traditional dances and performing celebratory sword fights during weddings and other occasions, according to the troupe's leader. (Photo by Muhammad Hamed/Reuters)

Vehicles pass through the heavy fog and air pollution that cover Skopje valley in the early morning, in Skopje, The Former Yugoslav Republic of Macedonia, 14 December 2017. According to media reports, Skopje is considered one of the most polluted cities in the world. (Photo by Georgi Licovski/EPA/EFE)

An exhausted and frustated migrant holds his head after he missed to get a place on a train heading to the Serbian border at the train station in Gevgelija, The Former Yugoslav Republic of Macedonia, August 13, 2015. From the beginning of the year to mid-June 2015, nearly 160,000 migrants landed in the southern European countries, mainly Greece and Italy, on their way to wealthier countries in Western and Northern Europe, according to estimates by the International Organization for Migration (IOM). (Photo by Georgi Licovski/EPA)