Mikel was called up by coach Samson Siasia for the country's campaign at Rio de Janeiro and he led the team to a bronze medal.
Following his return from the tournament, the midfielder was frozen out of Conte's squad, which made seek a greener pasture in the Chinese Super League with Tianjin Teda.
"For me, it was a decision I had to take because when the opportunity came up to either go to Rio or play for Chelsea," Mikel told the NFF media.
“I decided that Victor Moses, who was the younger and hasn’t played yet for the club, should stay back while I go to the Olympics.
"Victor stayed back and I went but when I got back the manager never spoke to me again and did not even put me in the team, so I had to leave the club.
"For me, my commitment to play for the national team will never change until I stop playing."
Nigeria are in Group B of the showpiece and they will begin their campaign for a fourth Afcon title against Burundi at the Alexandria Stadium on June 22.