Jordan's ambassador to the United Nations, Prince Zeid al Hussein, has entered the race to succeed Secretary-General Kofi Annan.
Jordan's government said it sent a letter to the world body, formally announcing the candidacy.
Zeid is the fifth person to declare a run for the seat, and the first Muslim to do so.
Mr. Annan will reach the end of his second, five-year term in December. The next U.N. chief is expected come from the Asia group that includes Jordan.
Other declared candidates are South Korea's Foreign Minister Ban Ki-Moon, U.N. Under Secretary for Public Affairs Shashi Tharoor who is from India, Thailand's Deputy Prime Minister Surarkiart Sathirathai and former U.N. disarmament chief Jayantha Dhanapala of Sri Lanka.
Some information for this report was provided by AFP, AP and Reuters.