In January 2010 he moved to Inter Milan in Italy. There Nwankwo first played in the youth team of the Italian master, before making his debut in the group stage of the Champions League 2010/11 season with a 1-3 defeat against Tottenham Hotspur in the first team of Inter. Shortly thereafter, he made his Seria -A debut with a 1-2 defeat against Chievo Verona.
End of January 2011 Nwankwo was loaned for the rest of the season 2010/ 11 at the Parma, who holds a part of the transfer rights of the young Nigerian. The Gialloblù Nwankwo was hoping for more operating time. Prior to his move to Parma and Catania Calcio and AC Cesena showed interest in him.
Also in the 2011/12 season was one of the squad Nwankwo of Parma, who also holds a part of the transfer rights of the Nigerian on, but was used only sporadically. In January 2012 he was loaned to AS Gubbio 1910 in the B series, where he played regularly and was able to achieve two goals.
In summer 2012, Nwankwo extended his contract with Inter Milan until 30 June 2015, but was immediately loaned out to Serie B club Calcio Padova, so that he can continue to develop his game. In February 2013 Nwankwo was borrowed for half a season to CFR Cluj in the Romanian Liga 1. In June 2013, the Parma FC Inter Milan acquired the remaining transfer rights to Nwankwo.
Nwankwo played in the U20 national team of Nigeria and took this to the Junior Football African Cup of 2009 in Rwanda in part. The choice of Nigeria finished 3rd.
Likewise Nwankwo participated at the Junior World Championship 2009 in Egypt, when the selection was eliminated in the second round against the German U-20 national team. He formed during the tournament together with Ibok Edet central defense and finished all four games of his team over the full duration. The Technical Study Group raises Nwankwo, who scored in the final group match against Tahiti, shown in the official tournament report as one of three players of his team and describes him as " central defender with good understanding of the game, organizer " and praised his " good position and passing game " as well as his ability to win the ball.
Nwankwo was a member of the Nigerian squad for the Africa Cup 2013 in South Africa. His team was able to win this tournament, with Nwankwo came off the bench in a game against defending champions Zambia.
He also takes with the Nigerian national team, he takes part in the qualifiers for the 2014 World Cup in Brazil.