"I am of course disappointed that Luis has decided his future is not with Fulham," manager Chris Coleman has said.
"He has been a great servant to the club and we all wish him well.
"However, I have always said that if a player is not happy playing for this club and expresses a desire to go, then I would be prepared to let him leave, and this was the case with Luis.
"Having discussed this with the chairman and the managing director, we believe it is in the best interest of the club to invest in players who are prepared to commit their future to us."
"We will continue to add strength and depth this window and, if necessary, the next, to ensure that we have a strong enough squad of players for the future to enable us to push on as a club, which remains our ambition."