France's President Francois Hollande (C) is greeted by people during his tour of the old quarters of Hanoi on September 6, 2016. Hollande is in France's former colony Vietnam to meet political and business leaders in a bid to boost ties with one of southeast Asia's fastest growing economies. / AFP PHOTO / POOL / Le HieuLE HIEU/AFP/Getty Images

France's President Francois Hollande (2nd R) visits a heritage house during his tour of the old quarters of Hanoi on September 6, 2016. Hollande is in France's former colony Vietnam to meet political and business leaders in a bid to boost ties with one of southeast Asia's fastest growing economies. / AFP PHOTO / POOL / Le HieuLE HIEU/AFP/Getty Images

France's President Francois Hollande (2nd L) is greeted by people during his tour of the old quarters of Hanoi on September 6, 2016. Hollande is in France's former colony Vietnam to meet political and business leaders in a bid to boost ties with one of southeast Asia's fastest growing economies. / AFP PHOTO / POOL / Le HieuLE HIEU/AFP/Getty Images

France's President Francois Hollande (front 2nd L) is guided by professor Ngo Bao Chau (C) during his tour of the old quarters of Hanoi on September 6, 2016. Hollande is in France's former colony Vietnam to meet political and business leaders in a bid to boost ties with one of southeast Asia's fastest growing economies. / AFP PHOTO / POOL / Le HieuLE HIEU/AFP/Getty Images

France's President Francois Hollande (5th L) and professor Ngo Bao Chau (3rd L) talk with youths at Cong Cafe during his tour of the old quarters of Hanoi on September 6, 2016. Hollande is in France's former colony Vietnam to meet political and business leaders in a bid to boost ties with one of southeast Asia's fastest growing economies. / AFP PHOTO / POOL / Le HieuLE HIEU/AFP/Getty Images

France's President Francois Hollande (L) talks with French tourists during his tour of the old quarters of Hanoi on September 6, 2016. Hollande is in France's former colony Vietnam to meet political and business leaders in a bid to boost ties with one of southeast Asia's fastest growing economies. / AFP PHOTO / POOL / Le HieuLE HIEU/AFP/Getty Images

France's President Francois Hollande (L) and Vietnam's National Assembly's Chairwoman Nguyen Thi Kim Ngan (R) pose for a photo during a meeting at Ba Dinh hall in Hanoi on September 6, 2016. Hollande is in France's former colony Vietnam to meet political and business leaders in a bid to boost ties with one of southeast Asia's fastest growing economies. / AFP PHOTO / POOL / KHAMKHAM/AFP/Getty Images

France's President Francois Hollande (L) and Vietnam's National Assembly's Chairwoman Nguyen Thi Kim Ngan (R) attend a meeting at Ba Dinh hall in Hanoi on September 6, 2016. Hollande is in France's former colony Vietnam to meet political and business leaders in a bid to boost ties with one of southeast Asia's fastest growing economies. / AFP PHOTO / POOL / KHAMKHAM/AFP/Getty Images