Nigeria President Muhammadu Buhari on Tuesday offered a symbolic apology to the deceased winner of the 1993 democratic election that was annulled by the military.
The apology comes as Buhari is campaigning for a second term in office after making history in 2015 as the first opposition candidate in the country to unseat a sitting president.
Nigeria, which ended military rule in 1999, has suffered from a series of military coups since winning independence from Britain, including one led by Buhari in 1983.
Buhari ruled as military head of state until 1985, when he was toppled by General Ibrahim Babangida.
While in office, Buhari, a 75-year-old former general, has worked to assure Nigerians he is committed to democracy.
Wealthy businessman Moshood "MKO" Abiola was coasting home to victory when the results of the election were voided by military dictator Babangida.
"I tender the nation's apologies to Chief MKO Abiola," for the cancellation of the June 12, 1993 election, Buhari said during an event in honor of the politician who died in July 1998.
While observing a minute's silence in memory of Abiola and other pro-democracy heros who died during the struggle, Buhari said "Nigeria will no longer tolerate such perversion of justice."
The government said that from next year, June 12 would be a public holiday and commemorated as "Democracy Day" instead of May 29, the date marking Nigeria's return to civil rule in May 1999.
Abiola, a Muslim businessman from the Yoruba-dominated southwest, was arrested in 1994 for declaring himself president.
He died mysteriously on July 7, 1998 as talks got under way for his release.