CALGARY -- The head of the United Nations is to speak at the University of Calgary on Friday.

The university says UN Secretary-General Ban Ki-moon will give a speech to mark International Youth Day.

His speech is entitled "A call to youth: the UN in Canada in a changing world."

Ban has been UN Secretary-General since 2007.

Following his speech he is expected to answer questions from students and guests.

Only those who are invited will be allowed to attend the event.