Dancers perform at a Carnival parade in Les Cayes, Haiti, Tuesday, February 28, 2017. Haiti's three-day Carnival festivities have brought rum-fueled parties, imaginative costumes and high-energy dance music to a southern city that's still recovering from last year's punishing Hurricane Matthew. (Photo by Dieu Nalio Chery/AP Photo)

Roped up climbers leave the summit of Breithorn at 4,164 metres (13,661 feet) on the ridge marking the border with Switzerland (left) and Italy in the Alpine resort of Zermatt August 4, 2014. Switzerland will vote on November 30 on an initiative from the group Ecopop which proposes a cap on the number of immigrants. The group says it is motivated by concerns about a lack of living space exerting too much pressure on the land and natural resources, rather than by opposition to foreigners. (Photo by Denis Balibouse/Reuters)

People in Mexico wave at U.S. Border Patrol agents on horseback patrolling the U.S.-Mexico border fence near San Diego, California, U.S., November 10, 2016. (Photo by Mike Blake/Reuters)

A young migrant cries as she waits to cross the Greek-Macedonian border, near the village of Idomeni, Greece March 3, 2016. Thousands of refugees and migrants wait on the border between Greece and Macedonia and about 30,000 refugees and other migrants are stranded in Greece, with 10,000 at the Idomeni border crossing to Macedonia. (Photo by Marko Djurica/Reuters)

Girls cry as they get separated from their family at the border line dividing Macedonia and Greece August 21, 2015. At least 1,000 migrants and refugees pressed against Macedonian police lines on the Greek-Macedonian border on Friday and at least 10 people appeared to faint in the crush. People could be heard screaming and medical workers raced to treat those who passed out or were hurt. The crush ensued after police let several hundred through into Macedonia, having kept them out since Thursday under an emergency decree. (Photo by Ognen Teofilovski/Reuters)

Buildings in Nogales, Mexico (R) are separated by a border fence from Nogales, Arizona, United Sates, October 9, 2016. Building a wall along the U.S.- Mexico border has been a contentious subject in this year's U.S. presidential election. In parts of California and Arizona, a wall already exists. It runs across rocky deserts, flowing sand dunes and miles of agricultural land. (Photo by Mike Blake/Reuters)

A protester clashes with a police officer in Athens' central Syntagma (Constitution) Square in this June 15, 2011 file photo. Greece triggered the regional financial crisis in 2009 when a far higher budget deficit than previously calculated emerged. The collapse of talks with creditors in Paris last November set off a month-long sequence of events leading to elections this week and proving Greece is still the region's weak link. The vote is expected to be won by Syriza, a far-left party opposed to the bailout, worrying investors and creditors alike. (Photo by Yannis Behrakis/Reuters)

A pro-Russian supporter with the Russian national flag on her shoulders takes part in a meeting in Simferopol, March 6, 2014. Crimea's parliament voted to join Russia on Thursday and its Moscow-backed government set a referendum within 10 days on the decision in a dramatic escalation of the crisis over the Ukrainian Black Sea peninsula. (Photo by Vasily Fedosenko/Reuters)