U.S. First Lady Melania Trump smiles as she holds a football thrown to her by U.S. President Donald Trump during his joint news conference with Russia's President Vladimir Putin after a meeting in Helsinki, Finland, July 16, 2018. (Photo by Kevin Lamarque/Reuters)

In this Thursday, July 19, 2018, photo, a Syrian shopkeeper spraying water as waits for customers at the Hamadiyah market, named after the 34th Sultan of the Ottoman Empire Abdul Hamid II, in the Old City of Damascus, Syria. The celebratory mood in government-controlled areas stems from successive military advances in the past year and an impression that President Bashar Assad, with massive support by unwavering allies Russia and Iran, has won the war or at least militarily defeated the opposition trying to topple him. (Photo by Hassan Ammar/AP Photo)

A handout photo made available by Limex Images of Pete McLeod of Canada (R) and Kirby Chambliss of the United States flying over the city of Kazan prior to the fifth stage of the Red Bull Air Race World Championship in Russia on August 22, 2018. (Photo by Joerg Mitter/EPA/EFE/Limex Images)

A fisherman throws a net for catching fish with his wife in Yanhu fisherman village near Yangzhou, Jiangsu province, China, 18 October 2018. (Photo by Aleksandar Plavevski/EPA/EFE)

A sandstorm hits the city of Zhangye in Gansu province, China on November 27, 2018. (Photo by Reuters/China Stringer Network)

A military cadet gets help from a colleague to adjust her hair before taking part the military parade in Bucharest, Romania, Saturday, December 1, 2018, as thousands turned out Saturday to celebrate 100-years since Romania became a modern-day state, amid concerns about rule of law and the state of democracy. Crowds braved temperatures of minus 5 Celsius (23 Fahrenheit) to watch the military parade of troops, tanks and military vehicles. (Photo by Vadim Ghirda/AP Photo)

Thai LGBT community participates in Gay Freedom Day Parade in Bangkok, Thailand on November 29, 2018. (Photo by Soe Zeya Tun/Reuters)

Tourists take photos from a panoramic viewing deck on Victoria Peak in Hong Kong, China, 26 January 2019. Hong Kong has been ranked the world's freest economy by the Heritage Foundation, a conservative research and educational institution based in Washington, for the 25th consecutive year, but the researchers also said the judiciary had become less effective. (Photo by Jerome Favre/EPA/EFE)