All are reported to be keen to acquire the services of current Danish footballer of the year.
The Dutch champions' technical director Marc Overmars confirmed the 20 year old has refused to extend his current deal, which runs out in the summer of 2014.
He said: "Christian has informed us that he doesn't want to sign a new contract right now. I think he and his agent want to see what opportunities present themselves this summer.
"We want him to stay here for at least two more years, but the day he leaves us, he will be ready to play for the very best.
"He's a player even the biggest clubs in the world could do with having in their squad."