US Defense Secretary James Mattis will make his first overseas trip to South Korea and Japan next week which is considered as the two top critical allies of America in the Asia Pacific region, the Pentagon has said. <br/><br/>Mattis's will visit Seoul and Tokyo between February 1 and February 4. Departing on February 1, Mattis will begin his trip in South Korea, where he will meet Defence Minister Han Min Koo and other senior Korean officials.<br/>On February 3, Mattis will travel to Tokyo for meetings with his Japanese counterpart Tomomi Inada and other senior Japanese officials. In the statement, the Pentagon described Japan and South Korea as the critical allies of the US.