The experienced goalkeeper announced in May that he will leave Camp Nou at the end of the season when his contract expires, ending his lengthy association with Barca, with whom the 32-year-old has won six La Liga titles and the UEFA Champions League three times.
Marc-Andre ter Stegen and Pepe Reina have both been linked with a move to the Catalan giants and while Zubizarreta is confident that a new first-choice stopper will be announced soon, he has stopped short of naming Valdes' successor.
"I already know the name of the goalkeeper who is going to replace Valdes and he's practically already signed," he told Catalunya Radio.
"We just have to give it a little more time, before we make the announcement."
Zubizarreta, himself a former Barca goalkeeper, expects head coach Gerardo Martino to have a busy close-season after Carles Puyol announced that he would also leave at the end of the current campaign.
"We knew that Victor Valdes wasn't going to stay, now we know that Carles Puyol isn't going to either," he added.
"They have been two obvious references in our squad.
"Just taking these two players into account, I would say that it's already now more than the tweaks we had envisaged."
