In 718 he was promoted to Ippon (First Order of an Imperial Prince) and in the following year, 719, he and his younger paternal half-brother Imperial Prince Niitabe were ordered by the Empress Gensho to support Crown Prince Obito.
養老2年（718年）、一品の位階に昇叙され、翌養老3年には元正天皇より異母弟の新田部親王と共に皇太子首皇子の補佐を命じられた。