Manchester United manager Louis van Gaal has refused to rule out the possibility of signing goalkeeper Victor Valdes.
Manchester City boss Manuel Pellegrini says he is confident that England goalkeeper Joe Hart will sign a new contract.
Rafael van der Vaart insists he wants to stay at Spurs but hasn't ruled out a move to Schalke.
The 29-year-old former Hamburg midfielder has been linked with a return to Germany, where his wife still works.
Asked about the prospect of joining Schalke, Dutchman Van der Vaart told Bild: "I don't know. Actually, I want to stay at Tottenham. But, in football, you never know."
Pointing out he never expected to join Real Madrid or Spurs in the way he did, he added: "I spent three years living in Hamburg and had a wonderful time at HSV.
"My wife, Sylvie, works there and we have many friends who live in your country."