However, fearing that Silla would invade Wakoku due to the momentum gained in unifying the Korean Peninsula, Wakoku kept reinforcing their defensive measures along the sea coast, and although there was exchange between the two countries, their relations deteriorated after the enthronement of Emperor Jito.
しかし、新羅が朝鮮半島統一の勢いを駆って侵攻して来る事を恐れ、海岸の防備を固めるなどを怠らず、両国の関係は持統天皇即位後、交流はあるものの、次第に悪化する事になる。