The President, represented by Mr Boss Mustapha, Secretary to the Government of the Federation (SGF), gave the charge on Wednesday in Abuja at the handing over of athletes to the Nigeria Olympic Committee (NOC) and farewell ceremony for Team Nigeria to the Games.
Buhari, however, stressed on the need for the athletes to compete fairly and without any form of doping infractions at the Games.
The President said everything had been put in place by the Federal Government to ensure adequate preparation and welfare for the athletes and officials.
“Let me assure you that the Federal Government is fully committed to our successful participation in the African games and will ensure that the welfare of the team is adequately taken care of.
“I want to charge all athletes and team officials going to the Games to be worthy ambassadors of our great country, both on the field of play and outside the sports arena.
“I, therefore, urge you to keep the integrity of our nation intact by competing clean and fair, devoid of any form of doping at the African games,” he said.
Earlier, NOC President, Habu Gummel, said that the event marked the climax of the intensive preparations of the athletes ahead of the Games.
Gummel assured the Federal Government that the contingent would do the nation proud as the giant of Africa.
Permanent Secretary, Ministry of Youth and Sports Development Olusade Adesola urged the 462 athletes and officials for the Games to exhibit high level discipline and dedication at the Games.
High point of the event was the symbolic handing over of the Nigerian flag by Mustapha to Gummel and the farewell for the athletes.
The bulk of the Nigerian contingent is expected to depart Nigeria for the Games on Thursday via a chartered flight.
The 12th African Games will hold in Rabat, Morocco from Aug. 19 to Aug. 31.
Team Nigeria finished second in the last edition of the Games in Congo Brazzaville in 2015.