Two children brought to Japan by their Japanese mother returned to their home in Canada last month under a treaty settling cross-border custody disputes, Foreign Ministry officials said.
It was the second departure of children from Japan under the 1980 Hague Convention on the Civil Aspects of International Child Abduction since Tokyo finally joined the pact in April.
In October, a boy brought to Japan by his Japanese mother returned to Germany after his German father sought his return under the pact.
The November case also marked the first return of children negotiated under an alternative dispute resolution system that seeks to settle problems without resorting to the courts.
After the children's Canadian father appealed to the ministry for help, it told them about a mediation system offered by the Tokyo Bar Association that was used to negotiate the return of his 6-year-old boy and 4-year-old girl. The ministry paid for the mediation service, it said Friday.
The children, dual citizens of Canada and Japan, had been living in Canada until their mother took them to Japan in March this year.
Parents or guardians who fail to reach an agreement through mediation can take the case to court. Rulings on such requests are made by family courts in Tokyo or Osaka.
The first such ruling was made by the Osaka Family Court last month and ordered a mother to return her daughter to Sri Lanka. She appealed the ruling to the Osaka High Court.
The Hague convention stipulates that if a parent takes a child under 16 from his or her country of habitual residence to another member state, the other parent can file a case for the child's return.