(FILES) This file photo taken on July 27, 2016 shows Philippine President Rodrigo Duterte (R) greeting US Ambassador to the Philippines Philip S. Goldberg (L) as US Secretary of State John Kerry looks on during his visit to the Malacanang presidential palace in Manila. The Philippines' firebrand President Rodrigo Duterte has sparked a fresh diplomatic row with his colourful language, calling the US ambassador "gay" in comments that prompted Washington to summon Manila's envoy to complain. In the latest of series of tirades, Duterte used a local Tagalog language homophobic slur to express his displeasure with US Ambassador Philip Goldberg in televised comments made on August 5, 2016. / AFP PHOTO / POOL / Aaron FavilaAARON FAVILA/AFP/Getty Images