The United Nations Food and Agriculture Organisation has named Sheikha Fatima bint Mubarak an extraordinary goodwill ambassador, according to WAM, the state news agency.
Sheikha Fatima, the chairwoman of the General Women's Union and the Family Development Foundation, is the widow of Sheikh Zayed, the founder of the nation.
The UN organisation announced the decision at its headquarters in Rome to mark World Food Day. Rashid Ahmed bin Fahad, the UAE Minister of Environment and Water, and Abdulaziz al Shamsi, UAE Ambassador to Rome, attended, as well as other ministers and officials.
Sheikha Fatima was given the title in recognition of her efforts and support for women's causes, both in the region and internationally, said Jacques Diouf, the agency's general director.
She has played a large role in eradicating illiteracy and promoting women's education and rights, Dr Diouf said.
Sheikha Fatima is the fourth person to receive the title of extraordinary ambassador. The first ladies Suzanne Mubarak of Egypt, Maria Gloria Penayo de Duarte of Paraguay and Margarita Cedeno de Fernandez of the Dominican Republic have also received the honour.