Buhari urged Nigerians to accept the recognition in good faith.
The president said this after he officially conferred the post-humous title of Grand Commander of the Order of the Federal Republic (GCFR) on the late Chief MKO Abiola on Tuesday, June 12, 2018.
He also awarded Abiola's 1993 running mate Baba Gana Kingibe with a Grand Commander of the Order of the Niger (GCON) title, an award he also bestowed on the late Chief Gani Fawehinmi (SAN) for his human rights agitation for the actualisation of the June 12th elections.
At the investiture ceremony which took place at the Presidential Villa on Tuesday, Buhari urged Nigerians to accept the recognition in good faith.
The president said the recognition of the events of June 12 is not to reopen old wounds but to correct a wrong that was done to the free will of the Nigerian people.
He said, "Today, I'm very happy to be present and to preside over the commemoration and investiture marking the formal federal government recognition of June 12 as national democracy day.
"The decision and this event is not meant to be and is not an attempt to open old wounds but to put right a national wrong. Nigerians, of their own free will, voted for late Chief MKO Abiola and Ambassador Baba Gana Kingibe, the presidential flag bearer and running mate of the Social Democratic Party in the 1993 elections.
"The government of the day inexplicably cancelled the elections when it was clear who were winning. We cannot rewind the past, but we can at least assuage our feelings, recognise that a wrong has been committed and resort to stand firm now and in the future for the sanctity of free elections. Nigerians will no longer tolerate such perversions of justice.
"This retrospective and post-humous recognition is only a symbolic token of redress and amd recompence for the grievous injury done to the peace and unity of our country.
"Our decision to recognise and honour June 12 and its actors is in the national interest. It is aimed at starting a national healing process and reconciliation of the 25-year festering wound caused by the annulment of the June 12 elections. I earnestly invite all Nigerians across all our national divide to accept it in good faith.
"Our action today is to bury the negative side of June 12; the side of ill-feelings, hate, frustation and agony. What we're doing is celebrating and appreciating the positive side of June 12.
"It's a June 12 which reinstates democracy and freedom. It's a June 12 that overcomes our various divides and the June 12 that producess unity and national cohesion. This is the June 12 we're celebrating today and we'll nuture it to our next generations."
The president further apologised to the family of the late Abiola, on behalf of the federal government, for his death in the struggle to hold on to his mandate.
Buhari said, "Accordingly, on behalf of the federal government, I tender the nation's apology to the family of late MKO Abiola who got the highest votes and to those that lost their loved ones in the course of June 12 struggle."
At the end of his speech, the president asked everyone in the Conference Hall to stand for a one-minute silence in honour of MKO Abiola, Fawehinmi, and all those who lost their lives in the aftermaths of the annulled election.