(150725) — NAIROBI, July 25, 2015(Xinhua) — U.S. President Barack Obama speaks during a joint press conference with Kenyan President Uhuru Kenyatta in Nairobi, Kenya, July 25, 2015. Kenya and the U.S. on Saturday reaffirmed their commitment on security cooperation and in the war against terrorism to help prevent future terror attacks in the East African nation. (Xinhua/Sun Ruibo)