A plan has emerged within the government to enable female members of the imperial family to keep their royal status even if they marry a commoner, sources with knowledge of the matter said Sunday, thus maintaining their branches of the family.

The current rules require female royals to give up their imperial status when they marry a commoner, causing the family to become progressively smaller.

The dwindling number of imperial family members has again come into focus ahead of the expected marriage later this year of Princess Mako, 29, a niece of Emperor Naruhito, to her boyfriend, Kei Komuro.