A senior UN official says armed conflicts and natural disasters have resulted in a massive humanitarian crisis affecting one in 22 people around the world.

Joyce Msuya, Assistant Secretary-General of the UN Office for the Coordination of Humanitarian Affairs, spoke to NHK on Friday in Japan.

Msuya cited Ukraine, Myanmar, Syria and Afghanistan as countries that have experienced a combination of conflict and disaster. She said the number of people requiring humanitarian assistance is rising rapidly.

Msuya pointed out that in Sudan, fighting between the army and a paramilitary group has uprooted 1.8 million people. But she said relief supplies are not reaching mothers and children due to poor security, while UN organizations there are being looted or destroyed.

Msuya says Myanmar's military rulers have impeded efforts to help areas devastated by a deadly cyclone last month.

Msuya says Japan has a wealth of knowledge and experience regarding disaster response.

She added that she was touched by the generosity of the Japanese people who joined the rescue and relief effort in Turkey following a series of massive earthquakes in February.

Japan is this year's chair of the Group of Seven nations. Msuya is urging the country to show leadership in the global push to provide humanitarian assistance.