The hard-liners of Japan suggested to Munenori TERASHIMA, Gaimu-taifu (post of Foreign Ministry) to dispatch a warship to inshore of Korea in the name of measuring the coastline and investigating passages (to harass them as well as Matthew [Calbraith] PERRY did), and he accepted it under the approval of Sanetomi SANJO, the Grand Minister, and Tomomi IWAKURA, Minister of the Right.
強硬派から（マシュー・ペリー同様嫌がらせのために）測量や航路研究のためとし朝鮮近海に軍艦を派遣して軍事的威圧を加える案が出ると、外務大輔の寺島宗則は太政大臣三条実美や右大臣岩倉具視の了承を得てこれを承認した。