Japan's lower and upper house speakers on Friday compiled a draft consensus on a law revision to maintain the number of imperial family members, the lower house speaker said, amid longstanding concerns over a stable imperial succession.

The document, based on views from all parties, will be presented as a draft "consensus of the legislature" at a meeting Monday of all 13 parliamentary parties and groups, House of Representatives Speaker Eisuke Mori told reporters after discussing the issue with the vice speaker and their House of Councillors counterparts.

The proposed revision of the 1947 Imperial House Law, which currently only allows a male who has an emperor on his father's side to succeed the throne, would permit the imperial family to adopt men from 11 former branch families while allowing female members to retain their imperial status after marriage.

If approved at the following meeting on Wednesday, the consensus will be presented to Prime Minister Sanae Takaichi, after which her government will draft and submit a revision bill. The legislation could be enacted by July 17 when the current parliamentary session ends, according to sources familiar with the matter.

"Having carefully taken each party's views into consideration, we have crafted what we believe is best," said Mori, a veteran lawmaker from the ruling Liberal Democratic Party led by Takaichi.

"We sincerely ask for the understanding and support of all parties and groups," Mori added, but he declined to make the draft consensus public as it has yet to be presented to the parties.

Concerns over securing a stable imperial succession have grown more acute as there are only three heirs to 66-year-old Emperor Naruhito -- his younger brother Crown Prince Fumihito, 60, his nephew Prince Hisahito, 19, and his uncle Prince Hitachi, 90.

Mori has discussed the issue with House of Councillors President Masakazu Sekiguchi, an LDP lawmaker, and the lower and upper chambers' vice speakers, Keiichi Ishii of the Centrist Reform Alliance and Tetsuro Fukuyama of the Constitutional Democratic Party of Japan -- both opposition parties.

After hearing from all parties and groups since April, the four lawmakers had struggled to compile a draft consensus, with some CDPJ members expressing doubt about granting imperial family status to men from former branch families who have grown up as commoners.

According to the sources, the draft consensus says the wishes of female imperial family members on whether to retain or relinquish their status after marrying commoners should be respected, while leaving unresolved whether their husbands and children would also obtain imperial status.

The draft also says that the adoption of male members of the former branch families, which is prohibited under the current law, would be reconsidered at fixed intervals if deemed necessary, the sources said.

© KYODO