Succession to the Japanese throne
The current succession to the Japanese throne is governed by the Imperial Household Law, which stipulate agnatic primogeniture. Japanese government publicly responded to criticism from a committee of the UN which had voiced concerns about the exclusion of women from the line of succession to the Chrysanthemum Throne, stating that the succession system is a fundamental aspect of the country’s traditions and should not be subject to criticism.
Source: Wikipedia — Succession to the Japanese throne (CC BY-SA 4.0)