A Saudi soldier fires a mortar towards Houthi movement position, at the Saudi border with Yemen April 21, 2015. (Photo by Reuters/Stringer)

A man arranges a display of cacti during preparations for the RHS Chelsea Flower Show in London, Britain May 21, 2016. (Photo by Neil Hall/Reuters)

Iraqi forces gather during an operation to attack Islamic State militants in Mosul, Iraq, October 21, 2016. (Photo by Reuters/Stringer)

A boy jumps over a puddle of water on the outskirts of Havana, Cuba March 21, 2016. (Photo by Ueslei Marcelino/Reuters)

Villagers take part in Kolyada holiday celebrations in the village of Martsiyanauka, east of the capital Minsk, January 21, 2015. Local residents took part in the celebrations to mark the end of a pagan winter holiday Kolyada, which over the centuries has merged with Orthodox Christmas celebrations. (Photo by Vasily Fedosenko/Reuters)

Young women flash the victory sign in front of a bonfire as Turkish Kurds gather during Newroz celebrations for the new year in Diyarbakir, southeastern Turkey, on March 21, 2017. Newroz (also known as Nawroz or Nowruz) is an ancient Persian festival, which is also celebrated by Kurdish people, marking the first day of spring, which falls on March 21. (Photo by Ilyas Akengin/AFP Photo)