Mr. Masahiko due to visit Yemen at the head of delegation in March 22.  A diplomatic source said the Japanese official will meet during a three-day visit a number of Yemeni officials and hold talks on enhancing bilateral relations between Yemen and Japan, and ways of enhancing them to serve the common interests of the two countries and peoples.  The source added that the Japanese vice Foreign Minister will visit the free zone in Aden to be acquainted with the investment opportunities and facilities provided to investors.