Iwobi played for England throughout the youth team levels before choosing the country of his birth.
He said on social media: "I will always have my respect for England, when I played for England they gave a great opportunity, they treat me very well.
"However, I feel like I am a true Nigerian, I grew up in the Nigerian culture and when I had the opportunity to go back I felt more at home playing for Nigeria.
"I felt at home playing for England as well.
"Of course it was difficult because I was very comfortable playing for England like it's where I've grown up. I grew up in the English roots so I knew how the system works.
"But when I had the opportunity to go and trial for the U23s is when I thought there was a lot of love for football - the way I was treated there - and these times I didn't have the profile I had today. I was really excited to play for the U23s.
"Even though the organisation may be a bit different to England, I really enjoy it. Even to this day I have no regrets."