Valencia expressed interest in the the Dutch international, but Hamburg sports director Dietmar Beiersdorfer recently revealed his side's reluctance to sell their star man.

However, the former Ajax ace is unhappy with his club's reaction to the Valencia bid.

"I still think I will play for Valencia and I'm going to keep fighting to do that even though there isn't much time left," Van der Vaart told Spanish daily AS.

"The (Hamburg) president promised me that if there were any interesting offers for me, especially from Spain, then they would look at them. He isn't keeping his word."

Van der Vaart is a key member of Huub Stevens' attack line, which was reinforced by the arrival of Egyptian striker Mohamed Zidan this summer.