The Belgian appears to set to be priced out of a move to Spurs by his Dutch club.
"The situation is not as I expected," Vertonghen told AT5. "Of course I'm happy with the guys here and the feeling with Ajax is still good. But being here gives me double feelings.
"Staying at Ajax would feel as a slap in the face. Everybody said that I'm ready for the next step. Right now it's a case between the clubs and agents.
"I've had no contact yet with the new coach [Villas-Boas]. But with my head I'm still at Ajax. I'm the captain, I won't be a rebel."