The failure of some 45 UN member nations to join the international Genocide Convention is both puzzling and shows their naivity, according to a UN special advisor.

Adama Dieng, special advisor to the UN secretary-general on the prevention of genocide, told the Human Rights Council this week that joining the convention was a "moral obligation towards humanity".

“What message are those states sending, 70 years after the adoption of the convention?" he asked at an event to mark the conventions 70th anniversary. "That genocide could never happen within their borders? That is being naïve. History has shown us time and again that genocide can happen anywhere.”

He urged the states to ratify the convention by 9th December, the anniversary date.

The 45 states yet to join the accord include 20 in Africa, 18 from Asia and seven from the Americas.

As many as 149 states have already either ratified or acceded to the convention, formally known as the Convention on the Prevention and Punishment of the Crime of Genocide. The convention was established in 1948 in the aftermath of World War II and the Holocaust.