In February, 1872, he had negotiations with Korea again with a letter under the name of Yoshiakira SO, who had been governor of Tsushima Domain and became Gaimu taijo (a post of the Ministry of Foreign Affairs, the fourth rank) after Haihan-chiken (abolition of feudal domains and establishment of prefectures), which stated that the diplomatic right had been transferred from Tsushima Domain to the Ministry of Foreign Affairs; however, the negotiation was unsuccessful.
翌明治5年（1872年）1月、廃藩置県により対馬藩主から外務大丞となった宗義達名で、外交権限が対馬藩から外務省に移管された旨の文書を携えて再び朝鮮国と交渉したが、不調に終わった。