Tokyo Gov. Yuriko Koike attends a talk a show on December 4, 2021 in Tokyo.

The Tokyo Metropolitan government will start a system that effectively allows same-sex marriage in Japan’s capital from April next year, the Kyodo news wire reported Tokyo Gov. Yuriko Koike as saying on Tuesday.

The local government for the city with a population of 14 million plans to introduce “same-sex partnership” after its local assembly unanimously called for such a move, Kyodo said.

Some local wards in Tokyo, as well as some other local municipalities, have already introduced a similar plan that officially recognizes same-sex couples. This gives them some of the same rights as married heterosexual couples.

But critics say LGBTQ couples still face disadvantages in areas such as taxation, even under such partnership arrangements.

A local court in Sapporo in northern Japan ruled in March that same-sex couples not being able to marry is “unconstitutional,” the first ruling in the country on the legality of same-sex marriage.

Homosexuality has been legal in Japan since 1880, and the country is relatively liberal compared with some other Asian nations. The only place in Asia to legalize same-sex marriage is Taiwan.

Additional reporting by CNN’s Chie Kobayashi and Julia Hollingsworth.