CAIRO (AP) — The head of the International Organization for Migration says leaders must prepare the world for more diversity as aging societies in the developed world and endemic youth unemployment in the developing world drive demographic trends.

Speaking at a meeting on migration in Cairo on Wednesday, IOM Director-General William Lacy says northern societies need workers while "we have a youthful, largely unemployed global south, with young people needing jobs."

He says the world is bound to become more diverse in terms of culture, ethnicity and religion.

He says, "Leaders who are not preparing their people for this, through public education, public information, and awareness-raising campaigns, just may not be doing their job."