TOKYO (Kyodo) -- The Japanese government is considering submitting to parliament next year a bill to legalize the use of birth surnames after marriage, rather than pursuing legislation to allow married couples the option to retain separate surnames, a government source said Wednesday.

In a country where married couples are required by law to share the same surname, the government led by Prime Minister Sanae Takaichi hopes the legalization will prompt wider acceptance of birth surnames by financial institutions and other entities as more women join the workforce and continue using their former surnames.

Former surnames alongside new surnames are currently allowed on official identification documents such as driver's licenses and passports. But about 30 percent of banks did not allow accounts to be opened under former surnames in 2022 over fears of money laundering, according to the government.

The bill, which the government aims to submit during the regular Diet session, is not expected, however, to address growing calls by business leaders and political parties, including the main opposition Constitutional Democratic Party of Japan, to introduce the option for married couples to retain separate surnames.

Takaichi, a staunch conservative and Japan's first female prime minister who took office in October, has been cautious about allowing the retention of separate surnames, with some in her ruling Liberal Democratic Party concerned that it would undermine family cohesion and traditional values.

Deputy Chief Cabinet Secretary Kei Sato told a press conference that the plan to submit a bill next year to legalize the expanded use of birth surnames was included in a coalition agreement signed in October between the LDP and the Japan Innovation Party.

"Based on the agreement, the government is carrying out the necessary discussions in coordination" with ruling lawmakers, Sato said.

As for whether to introduce a system allowing married couples to choose either the wife's or the husband's surname, Sato stressed the need to consider public opinion and the progress of discussions in the Diet.

The issue is among the most contentious in the nation, with the Justice Ministry saying it is unaware of any country other than Japan that requires couples, by law, to adopt the same surname upon marriage.

Japanese government data from 2024 showed that the wife adopts her husband's name in an overwhelming 94 percent of cases. The U.N. Committee on the Elimination of Discrimination against Women has repeatedly called on Japan to review the legal requirement.

Business leaders have also urged the government to swiftly introduce a system allowing married couples to choose separate surnames, arguing that women are burdened by procedural inconveniences, such as not being able to open bank accounts or obtain credit cards under the former surnames they use at work.

In May, Japan's parliament held its first deliberations in 28 years on legislation that would give married couples the option to keep different surnames, but the bill was never put to a vote during the session that ended in June.

The issue of retaining separate surnames has also been taken to court, with the Supreme Court's Grand Bench ruling in both 2015 and 2021 that the provision requiring a single surname for married couples is constitutional. In the 2015 case, five of the 15 justices found the prohibition on separate surnames unconstitutional, while four justices held the same view in 2021.