An international pact that sets procedures for settling cross-border child custody disputes will now be signed by Japan, after years of foreign pressure to do so.
At Friday's cabinet meeting, the government agreed to sign the 1980 Hague Convention that extends custody rights to non-Japanese parents whose children are moved to Japan by a former spouse.
The government's chief spokesman, Yukio Edano, told a news conference, "It is desirable to be consistent with rules of the international community," according to Jiji Press.
Parliamentary approval of the decision could come in the autumn, the Nikkei daily said in its online edition.
Japan is the only major industrial nation that has not signed the treaty.
Tokyo has been under pressure in recent years from the United States and other countries to accede to the treaty as Japanese courts almost never grant custody to foreign parents, particularly fathers, when international marriages break up.
Activists say that thousands of foreigners, mostly men, have been barred at some point from seeing children taken to Japan by estranged partners.
Prime Minister Naoto Kan is due to announce the plan when he attends a G8 summit in France next week, Japanese media reported.
Envoys from the United States, the European Union and nine other governments called on the Japanese foreign ministry last February to sign the treaty.
Last year the US House of Representatives approved a resolution condemning Japan's "abduction and wrongful retention" of children and urging the close ally to act immediately to resolve cases involving US parents.
The House resolution said 136 children were in Japan against the will of a US parent.