Japan's parliament on Wednesday approved an international treaty on child abductions after decades of pressure from the United States and other Western nations, AFP reports.
Japan is the only member of the Group of Eight major industrialised nations that has not ratified the 1980 Hague Convention, which requires nations to return snatched children to the countries where they usually reside.
Hundreds of parents, mostly men, from North America, Europe and elsewhere have been left without any recourse after their estranged partners took their half-Japanese children back to the country.
Unlike Western nations, Japan does not recognise joint custody and courts almost always order that children of divorcees live with their mothers.
US lawmakers have long demanded action from Japan on the issue, one of the few open disputes between the close allies. In February, Prime Minister Shinzo Abe promised action after White House talks with US President Barack Obama.
The upper house of parliament on Wednesday voted unanimously for Japan to join the treaty, following a similar move by the more powerful lower house last month.
But Japan must still clear various governmental and legislative hurdles before the Hague Convention can take full effect. The government has said it aims for final ratification by the end of this fiscal year -- March 2014.
A central authority will be set up in the foreign ministry to take charge of locating children who have been removed by one parent following the collapse of an international marriage, and to encourage parents to settle disputes voluntarily.
The newly enacted law will, however, allow a parent to refuse to return a child if abuse or domestic violence is feared, a provision campaigners say is vital, but which some say risks being exploited.
If consultations fail, family courts in Tokyo and Osaka will issue rulings.