Recovery operations were under way near the crash site around the town of Bishoftu, which is 60km (37 miles) south-east of the capital.
The plane was delivered to Ethiopian Airlines on 15 November last year, records show.
Who are the victims?
Mr Gebremariam told the news conference that passengers from more than 30 countries were on board the flight.
He said they included 32 Kenyans, 18 Canadians, nine Ethiopians, eight Italians, eight Chinese, eight Americans, seven Britons, seven French citizens, six Egyptians, five Dutch citizens, four Indians and four people from Slovakia.
Slovak MP Anton Hrnko later confirmed via Facebook that his wife and two children were on the plane.
Three Austrians, three Swedes, three Russians, two Moroccans, two Spaniards, two Poles and two Israelis were also on the flight.
There was also one passenger each from Belgium, Indonesia, Somalia, Norway, Serbia, Togo, Mozambique, Rwanda, Sudan, Uganda and Yemen.
Four people held United Nations passports, the airline said, and it believed some passengers could have been heading to a session of the UN Environment Assembly which begins in Nairobi on Monday.