The government will seek to lower the age of adulthood from 20 to 18 during the ordinary Diet session to be convened in January.

If approved, the planned change is expected to take effect in 2022 at the earliest after a transition period.

In 2009, the Legislative Council, an advisory panel to the justice minister, proposed an amendment to the Civil Code to lower the legal age of adulthood to 18 to facilitate greater youth participation in politics and bring Japan in line with other developed countries.

In 2015, the voting age was lowered to 18 under the revised Public Offices Election Law. Teenagers cast ballots in a national election for the first time in the election for the Upper House in July 2016.

The Civil Code amendment was originally set to be submitted to the extraordinary Diet session this autumn, but the dissolution of the Lower House --- for the Oct. 22 election ---on the opening day of the session dashed the plan. The lowering of the adulthood age is expected to be delayed from the initially envisaged 2021 start.

The planned amendment would allow 18-year-olds and 19-year-olds to marry and sign contracts to buy high-priced goods and services without parental consent.

But the government is expected to maintain the minimum age of 20 for smoking and drinking alcohol to avoid damage to the health of young people and impacts on high school education.