"Taking into consideration the escalating tension in the Middle East, it is necessary to strengthen our information gathering effort," Chief Cabinet Secretary Yoshihide Suga told a news conference, AP reported.
Citing Japan's heavy dependence on oil imports from the region, Suga added that "it is extremely important to secure the safe navigation of Japan-affiliated ships."
Despite being a US ally, Japan's troop dispatch is not part of a US-led coalition protecting Middle East waterways.
Under the plan, Japan will send about 260 Maritime Self-Defense Force personnel with a destroyer and a pair of P-3C reconnaissance aircraft, mainly for intelligence-gathering in the Gulf of Oman, the Arabian Sea and the Bab el-Mandeb Strait connecting the Red Sea and the Gulf of Aden.
Defense Minister Taro Kono issued an order for the troops to start preparing for the operation, which is planned for one year beginning early next year.
Kono is to visit Djibouti on the eastern coast of Africa and Oman this weekend to discuss Japan's mission. Japanese troops have been based in Djibouti as part of an international anti-piracy effort off the Somali coast, and a P-3C unit currently in that operation will be shifted to the new mission in January, he said.
Japan will stay away from the Strait of Hormuz.
Prime Minister Shinzo Abe explained the plan to Iranian President Hassan Rouhani when he visited Tokyo last week.
The Middle East supplies more than 80% of Japan's oil needs.
message end/