Japan's emperor is heading to the Philippines for a four-day visit to a country that suffered under Japanese occupation during World War II.

Emperor Akihito and his wife Empress Michiko departed for Manila from Tokyo's Haneda Airport on Tuesday morning.

The 82-year-old emperor will pay his respects at memorials for both the Philippine and the Japanese war dead.

Japan-Philippines relations have improved dramatically in the seven decades since the war. Japan has become a major aid donor to the Philippines, and the countries are deepening security ties in the face of China's military rise.

The emperor's trip follows visits to the World War II battle sites of Palau last year and Saipan in 2005. He also prayed for Japanese and U.S. war-dead in Iwo Jima in 1994.