Valdes tore his anterior cruciate knee ligament in Barcelona’s La Liga victory against Celta Vigo on Wednesday, and will now miss this summer’s World Cup in Brazil.
"Right now I'm not going to talk about possible replacements, because now is the time to bemoan Victor's injury,” said Del Bosque, speaking to El Primer Toque.
The timing of the injury is disastrous for the 32-year-old, who has already announced his decision to leave Camp Nou when his contract expires in June, meaning he has now played his final game for the club.
Valdes has spent his entire career with Barcelona having come through the club's famed La Masia youth ranks. He made his debut in 2002 and has since gone on to win the Champions League three times as well as six La Liga titles.