Japan's male-only succession rule should take precedence in discussions on how to achieve a stable imperial succession, Prime Minister Yoshihide Suga said on a radio program aired Sunday.

"Under current circumstances, male-only succession should be given priority," Suga said in a prerecorded radio show broadcast by Nippon Broadcasting System Inc., referring to the long tradition of male succession. The program was recorded on Dec. 18.

Suga's administration has said it will hold discussions on how to secure a stable imperial succession following calls from the Diet to address the issue.

The move comes amid concerns that the imperial household could run out of heirs. Currently, only three males are in line to succeed 60-year-old Emperor Naruhito — his younger brother Crown Prince Akishino, 55, the crown prince's son Hisahito, 14, and the emperor's uncle Prince Hitachi, 85.

The emperor and Empress Masako have a 19-year-old daughter, Princess Aiko. But the 1947 Imperial House Law states that only males in the paternal line can ascend to the chrysanthemum throne.

In a Kyodo News poll conducted last year, the public has shown support for women to ascend the throne.