"An offer from such a club is not there yet," he told Brabants Dagblad. "They will have to come to an agreement with Willem II to buy my contract, so I do not know whether the match against Vitesse on Sunday is my last for Willem II.
"A club that satisfies is not there yet, I feel very happy with Willem II for the time being."
On the Watford visit, Sol added: "They wanted to get to know me as a human being and show me the club. I would like to set myself up with a possible next step, which is certainly not what Watford is all about."