Migrants walk past graffiti at the port city of Piraeus, Greece on Monday, April 25, 2016. Around 3,500 migrants remain in Piraeus using tents, a warehouse and a terminal passenger building for shelter, as over 50,000 stranded refugees and migrants remain in the country. (Photo by Thanassis Stavrakis/AP Photo)





Afghan migrants play cards outside their tents under a bridge at the port city of Piraeus, Greece, on Monday, April 25, 2016. (Photo by Thanassis Stavrakis/AP Photo)





Afghan migrants use an outdoor water tap to wash in the port city of Piraeus, Greece, on Monday, April 25, 2016. Over 3000 migrants in Piraeus continue to sleep in tents, a warehouse and a terminal passenger building, as over 50,000 migrants remain in the country. (Photo by Thanassis Stavrakis/AP Photo)





Migrants and refugees gather near their tents set on the tracks of a railway station turned into a makeshift camp at the northern Greek border point of Idomeni, Greece, Monday, April 25, 2016. Many thousands of migrants remain at the Greek border with Macedonia, hoping that the border crossing will reopen, allowing them to move north into central Europe. (Photo by Gregorio Borgia/AP Photo)





A pot over a bonfire was placed on the tracks of a railway station turned into a makeshift camp, crowded by migrants and refugees at the northern Greek border point of Idomeni, Greece, Monday, April 25, 2016. (Photo by Gregorio Borgia/AP Photo)





A man walks on the tracks of a railway station turned into a makeshift camp crowded by migrants and refugees at the northern Greek border point of Idomeni, Greece, Monday, April 25, 2016. (Photo by Gregorio Borgia/AP Photo)





Two children gather poppies at a field next to a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A refugee sits at the entrance of his tent following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





Children play in a puddle following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A refugee walks under heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A refugee walks next to tents following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





Children play outside a tent following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





Two women stand next to tents at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A refugee carries a baby carriage as a young boy follows under heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





Heavy rainfall hits a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





Two refugee women dry their children after bathing them at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A woman washes her child at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





People are reflected in a puddle next to tents following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





People walk next to tents following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A girl walks in a puddle next to tents following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A baby is seen in its baby carriage following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A boy walks in a puddle next to tents following heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





Children play inside a train wagon next to a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





A refugee runs under heavy rainfall at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 24, 2016. (Photo by Alexandros Avramidis/Reuters)





Migrants and refugees gather by a fire at a makeshift camp at the Greek-Macedonian border near the village of Idomeni, Greece, April 25, 2016. (Photo by Alexandros Avramidis/Reuters)





Two refugees sit under a tree next to a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 25, 2016. (Photo by Alexandros Avramidis/Reuters)





Twenty day-old baby girl, born to Syrian parents at a refugee camp, is seen in a tent at a makeshift camp for migrants and refugees at the Greek-Macedonian border near the village of Idomeni, Greece, April 25, 2016. (Photo by Alexandros Avramidis/Reuters)





A child uses an umbrella to avoid rain falling on a fire at the northern Greek border point of Idomeni, Greece, Monday, April 25, 2016. Many thousands of migrants remain at the Greek border with Macedonia, hoping that the border crossing will reopen, allowing them to move north into central Europe. (Photo by Gregorio Borgia/AP Photo)





In this picture provided by the Office of Her Majesty Press Department, Queen Rania of Jordan, center, meets with refugees and migrants during her visit to Kara Tepe municipality camp in the Greek island of Lesbos, Monday, April 25, 2016. (Photo by Office of Her Majesty Press Department via AP Photo)





In this picture provided by the Office of Her Majesty's Press Department, Queen Rania of Jordan, center, touches an injured baby during her visit to Kara Tepe municipality camp in the Greek island of Lesbos, Monday, April 25, 2016. (Photo by Office of Her Majesty Press Department via AP Photo)





In this picture provided by the Office of Her Majesty's Press Department, Queen Rania of Jordan, center, listens to refugees and migrants during her visit to Kara Tepe municipality camp in the Greek island of Lesbos, Monday, April 25, 2016. (Photo by Office of Her Majesty Press Department via AP Photo)





A refugee peeks through a window as Queen Rania of Jordan (R) meets with Syrian refugee women during her visit at the Kara Tepe refugee camp on the island of Lesbos, Greece, April 25, 2016. (Photo by Alexandros Avramidis/Reuters)





A woman standing in front of a graffiti depicting the EU flag, holds her blankets at the end of a rainstorm at the northern Greek border point of Idomeni, Greece, Sunday, April 24, 2016. Many thousands of migrants remain at the Greek border with Macedonia, hoping that the border crossing will reopen, allowing them to move north into central Europe. (Photo by Gregorio Borgia/AP Photo)





A man holds a child as he walks on a muddy field at the end of a rainstorm at the northern Greek border point of Idomeni, Greece, Sunday, April 24, 2016. (Photo by Gregorio Borgia/AP Photo)