The highly-rated Danish international, who has attracted interest from the Premier League, said that he wants to prove himself at a "higher level".
"This summer I should leave," he told Sporten.dk. "That is the time when I have the biggest chance and I certainly hope that it will happen.
"It is still FCN who decide, but it is my plan to leave this summer."
Nordsjaelland are understood to have rejected a bid from Fulham for the defender last month, while Manchester United have been linked with him in the past.
Okore, born in the Ivory Coast, has played four international matches for Denmark.