However it was extremely difficult for Yoshioka to negotiate with Joseon that requested Japan to maintain the former diplomatic relationship through the Tsushima clan under the reign of Heungseon Daewongun who adopted a very nationalistic policy.
しかし興宣大院君政権下で極端な攘夷政策をとり、従来どおり対馬藩を通じた外交関係の維持を要求する朝鮮側との交渉は難航を極めた。