De Jong joined Barca for €75 million from Ajax in 2019 and while he has been a solid performer and a regular starter at Camp Nou, the Dutchman has not quite lived up to expectations.
With the likes of Pedri, Gavi, Nico Gonzalez and Sergio Busquets all competing for spots in midfield, Barcelona could view the 25-year-old De Jong as an opportunity to raise funds.
"He is a very important player, he has been a starter almost always. He is a fundamental footballer," said Xavi in a press conference on Saturday.
"Then there is the financial situation of the club, which we depend on. He should be a big part of this era of the club but we’ll see what happens."
LaLiga have set Barca’s spending limit at minus €144 million for the upcoming summer transfer window, after financial losses were found to be €242 million more than expected.
Barcelona president Joan Laporta said at the start of the season the club were €1.35 billion in debt, with LaLiga rules stating they would have to save four euros for every one spent on new additions.
"The circumstances of the club dictate everything," said Xavi. "We depend on the financial situation. In a few days we will know where we are and we have to start planning now."
Barca are, though, interested in Robert Lewandowski, the 33-year-old striker who said on Saturday he will not be extending his Bayern Munich contract, which expires in June 2023.
Asked about buying older players, Xavi said: "It doesn't stop me. I signed Dani Alves at 38. It’s not about age, it’s about performance."