With respect to political situations after the coming of Kurofune, Nariyuki concurred with Nariakira MITO arguing against the charter of the Treaty of Amity and Commerce between the United States and Japan.
黒船来航以来の政局にあたっては水戸斉昭と同調し、日米修好通商条約締結の勅許も不可を唱えた。