Manchester United manager Van Gaal decided not to comment on reports linking Victor Valdes with a move to Beşiktaş.
“When we want to do announcements, we shall do it, not when you ask us” he said, as reported by the Mirror.
The Spain international and World Cup winner is expected to leave United over the summer after falling out with Van Gaal over the summer.
Valdes has fallen down the pecking order behind first-choice keeper Sergio Romero and David De Gae.
Beşiktaş have agreed terms with Valdes sources close to the club told Turkish-football.com.
The experienced is expected to arrive in Turkey over the next few days to undergo a medical. The Black Eagles are concerned that Valdes may have an injury and want to carry out tests before signing him.
Valdes would become the third Manchester United player to join the Turkish league this summer. Robin van Persie and Luis Nani both joined Fenerbahçe on three-year deals last month.
The Black Eagles will compete in the Europa League Group A this summer against Sporting Lisbon, Lokomotiv Moscow and Skanderbeu.