Spain midfielder Xavi has spent his entire career at Camp Nou, but talk of a move away from the Catalan club has intensified.
A host of clubs have been linked with a move for the 34-year-old and the arrival of Ivan Rakitic from Sevilla has raised more questions over the playmaker's future.
Speaking at a press conference to introduce Rakitic as a Barca player, Zubizarreta revealed that he is in the dark as to whether Xavi will prolong his stay at the club and plans to hold talks with the club stalwart.
He said: "We are talking permanently with Xavi, we spoke to him before he went to the World Cup. He also wants the time to think, that's Xavi Hernandez, he's got every right to analyse things as he wants to do.
"He's our player, when he comes back from his holidays we'll sit down and we'll talk again. Any news he gives us will be good. If he decides to stay that will be fantastic news, if he decides that it might be the time to retire then we will treat that as well as we can.
"Time will tell, he's been at the club a long time, he owes us nothing. But obviously as soon as we've come to any specific decision then we will let you know. For the time being he's still there, he's still in the team.
"Essential, is anybody essential? We are talking about one of the key members of the team who has participated in one of the great eras at this club.
"We are not talking any old player, we're talking about somebody who is very special. We've been very open with Xavi in our conversations recently, we've been very transparent about things.
"If Xavi stays here he'll be competing with others for a place in the team, but if Xavi decides to explore other options we will respect that."
Xavi stated earlier this year that he plans to see out his career with Barca.