US First Lady Michelle Obama touches the nose of US President Barack Obama before he welcomes Singapore Prime Minister Lee Hsien Loong at the White House on August 2, 2016 in Washington, DC. / AFP PHOTO / Brendan SmialowskiBRENDAN SMIALOWSKI/AFP/Getty Images

US First Lady Michelle Obama touches the nose of US President Barack Obama before he welcomes Singapore Prime Minister Lee Hsien Loong at the White House on August 2, 2016 in Washington, DC. / AFP PHOTO / Brendan SmialowskiBRENDAN SMIALOWSKI/AFP/Getty Images

US President Barack Obama welcomes Singapore Prime Minister Lee Hsien Loong at the White House on August 2, 2016 in Washington, DC. / AFP PHOTO / Brendan SmialowskiBRENDAN SMIALOWSKI/AFP/Getty Images

US Vice President Joe Biden stands with US Secretary of State John Kerry (3rdL) before US President Barack Obama welcomes Singapore Prime Minister Lee Hsien Loong at the White House on August 2, 2016 in Washington, DC. / AFP PHOTO / Brendan SmialowskiBRENDAN SMIALOWSKI/AFP/Getty Images

WASHINGTON, DC - AUGUST 1: U.S. President Barack Obama and Secretary of Veterans Affairs Robert A. McDonald walk down the stairs of Air Force One as he returns from Atlanta, Georgia on August 1, 2016 at Joint Base Andrew in Maryland. Obama delivered remarks at the 95th National Convention of Disabled American Veterans and participated in a private Democratic National Committee roundtable. (Photo by Olivier Douliery-Pool/Getty Images)

WASHINGTON, DC - AUGUST 1: U.S. President Barack Obama walks down the stairs of Air Force One as he returns from Atlanta, Georgia on August 1, 2016 at Joint Base Andrew in Maryland. Obama delivered remarks at the 95th National Convention of Disabled American Veterans and participated in a private Democratic National Committee roundtable. (Photo by Olivier Douliery-Pool/Getty Images)

WASHINGTON, DC - AUGUST 1: U.S. President Barack Obama exits Air Force One as he returns from Atlanta, Georgia on August 1, 2016 at Joint Base Andrew in Maryland. Obama delivered remarks at the 95th National Convention of Disabled American Veterans and participated in a private Democratic National Committee roundtable. (Photo by Olivier Douliery-Pool/Getty Images)

A handout picture taken and released on August 1, 2016 by the Turkish Prime Minister Press Office shows Turkish Prime Minister Binali Yildirim (R) talking with with the Chairman of the Joint Chiefs of Staff of the United States, Joseph Dunford (L) at the Cankaya Palace in Ankara. Turkey admitted on August 1, 2016 there may have been some "unfair" treatment in its post-coup crackdown as it voiced anger at Germany for barring President Recep Tayyip Erdogan from addressing a rally in Cologne. Prime Minister Binali Yildirim told a top-ranking US general that his government remained committed to principles of law in its fight against coup plotters and called for Washington to extradite US-based preacher Fethullan Gulen "as soon as possible". During their meeting, the Turkish premier also told Dunford that the Turkish armed forces were fulfilling its duties "at full capacity" after the reshuffling in the wake of the coup attempt and said that cooperation continued "uninterrupted" with the US and other allies in the fight against terrorist groups including the Islamic State (IS) jihadists. / AFP PHOTO / TURKISH PRIME MINISTRE PRESS OFFICE / HAKAN GOKTEPEHAKAN GOKTEPE/AFP/Getty Images