Japanese Prime Minister Shinzo Abe has left on a tour of the Middle East and Africa, according to Japan's NHK World News Agency.He left Tokyo's Haneda airport for Oman on board a government plane on Thursday. He will also visit three African countries, Cote d'Ivoire, Mozambique and Ethiopia, before arriving back in Japan on Wednesday.Abe told reporters why he chose to visit the Middle East and Africa in his first overseas trip this year. He said Africa is a frontier for Japanese diplomacy and the Middle East is extremely important to Japan strategically and in terms of national security.He reiterated his commitment to what he describes as strategic diplomacy overlooking the entire globe.Prime Minister Abe hopes to use his talks with the leaders of the 4 countries to secure stable supplies of oil and natural gas for Japan. He also aims to bolster economic ties with them by creating an environment that will facilitate business activities and investment by Japanese firms.The prime minister is scheduled to deliver a speech on Tuesday at the headquarters of the African Union (AU) in Ethiopia. He will announce Japan's plans to assist African development.