Ghana's President Nana Akufo-Addo on Saturday hailed the late former UN Secretary General Kofi Annan as a consummate international diplomat who had brought immense pride to his country.

He ordered Ghana's national flag to be flown at half-mast across the country and in all of the country's diplomatic missions from Monday for one week.

Annan, who was also a Nobel Peace Prize laureate, died in hospital in Bern, Switzerland, in the early hours of Saturday aged 80.

Akufo-Addo said the government and people of Ghana were saddened by the news of the death of "one of our greatest compatriots".

"Consummate international diplomat and highly respected former Secretary General of the United Nations, Mr. Kofi Annan was the first from sub-Saharan Africa to occupy this exalted position. He brought considerable renown to our country by this position and through his conduct and comportment in the global arena," an official statement said.

"He was an ardent believer in the capacity of the Ghanaian to chart his or her own course onto the path of progress and prosperity."