The 21-year-old, who is expected to run down the final year of his contract at Ajax after refusing to sign a new deal, is thought to be regularly monitored by the Premier League outfits.
"Christian wants to play in the Premier League and we think he will do well there," a source at Ajax told the London Evening Standard. "The club had discussed the option of keeping him until the end of his contract but it makes sense now to sell.
"Liverpool and Spurs are scouting him almost every week. Arsenal are no longer interested and Man United are not on the scene. The club will not let him go cheaply so there is a long way to go but it seems likely he will move to Tottenham or Liverpool."
The Dutch club are thought to be valuing the midfielder at £14m.