ABIDJAN, Ivory Coast (AP) _ President Felix Houphouet-Boigny, Africa's longest-serving president, has won 99 percent approval in a referendum for a sixth term, the government announced Monday.

Interior Minister Leon Konan Koffi said on national television that more than 98 percent of the country's more than 3.5 million registered voters cast ballots. More than 99 percent of them endorsed another five-year term for Houphouet-Boigny, he added.

The government-controlled newspaper, Fraternite Matin, had earlier reported a 100 percent voter turnout.

Houphouet-Boigny has led this West African nation, the most prosperous in black-ruled Africa, since it gained its independence from France in 1960.

He ran as the sole candidate of his Ivory Coast Democratic Party - and with no running mate. The party congress, meeting earlier this month, eliminated the post of vice president. Party insiders, speaking on condition of anonymity, said the president was annoyed by infighting for the job.

The question of a successor for Houphouet-Boigny, 80, has been increasingly on the minds of the nation's eight million people. Houphouet-Boigny has said that like any other African chief, when he dies he will be replaced.

The party has reinstated a rule that the head of the country's national assembly will rule for 60 days, until an election is called, upon the death of the president. The national assembly president can be changed each year.

Houphouet-Boigny has shown no indication that he plans to step down or reduce his role in the government. He answered questions from local and foreign journalists for more than five hours on Oct. 14 in a gesture that appeared to be aimed at showing his stamina.

The country's economy has been improving this year with record harvests of coffee and cocoa. The New Mexico-sized nation leads the world in cocoa production and Africa in coffee exports. Its economy had been suffering from poor rains - it is on the fringe of the drought-hit Sahel - and poor prices for its commodities. But good rains fell this year, and prices have risen.

Houphouet-Boigny has built ''the economic miracle'' of the Ivory Coast, as it is often called, on free enterprise. He has focused on agriculture, and has kept close ties with France and other Western nations.