UNITED NATIONS, Dec. 2 (Xinhua) -- Contemporary forms of slavery remain a "grave and unresolved problem" across all continents, UN Secretary-general Ban Ki-moon warned on Wednesday, calling for greater efforts to address poverty and social inequalities which leave people vulnerable to enslavement.

    In a message marking the International Day for the Abolition of Slavery, observed annually on Dec. 2, Ban said that the list of new and old forms of slavery is "shockingly long."

    That list includes debt bondage, serfdom, forced labor, child labor and servitude, trafficking of persons and human organs, sexual slavery, forced marriage, the exploitation of prostitutes and the use of child soldiers.

    "The majority who suffer are the poor and socially excluded groups such as minorities and migrants," said Ban. "The overlapping factors of poverty, class and race create structural problems and cycles of marginalization that are hard to break."

    The secretary-general noted that gender inequalities, lack of education, desperation for work and demand for cheap labor also trap people in a life of subjugation, a vulnerability the global economic and financial crises threaten to heighten.

    "Combating slavery means not only its direct prohibition by law but also fighting against poverty, illiteracy, economic and social disparities, gender discrimination and violence against women and children," Ban said.

    The International Day for the Abolition of Slavery recalls the date of the adoption, by the General Assembly, of the United Nations Convention for the Suppression of the Traffic in Persons and of the Exploitation of the Prostitution of Others on Dec. 2, 1949.