Fabregas, who played under Wenger at Arsenal for eight years before returning to his native Catalonia in 2011, has been the subject of two bids from United.
However, both have been rejected by Barca and Wenger is certain the 26-year-old will not be leaving the Nou Camp in the current transfer window.
"What I know is that Fabregas will stay on more year, at least, in Barcelona," said the Frenchman. "That's the information I have.
"If that changes, I don't know. But that's what I've been told."
Wenger's comments come after new Barcelona manager Tata Martino said he would leave it up to Fabregas to decide whether he wanted to move to Old Trafford.
However, those comments are in contrast to those of Barca sporting director Andoni Zubizarreta who insists Fabregas is integral to the future plans of the Spanish champions.
"He has a contract with us," he told the club's website.
"We count on Cesc. I said that on the day of the presentation of Tito (Vilanova) and also with Tata (new coach Gerardo Martino).
"He's an extraordinary player who creates and finishes chances. We are delighted with him. He's the number four of Barca."
Gerard Pique and Andres Iniesta have also declared that their team-mate is not about to join United.
"Being as good a player as he is, it's normal that clubs will make offers for him, but he has always told me that he wants to stay at Barcelona and triumph here," Pique told a press conference, quoted in Sport.
The defender added: "That's always been his dream and I'm very happy that he's staying. I think he's never been in doubt."
Iniesta reiterated Pique's comments, underlining the importance of Fabregas to the team's future.
"He is indispensable, like everyone else in the squad," said the midfielder.
"He's fundamental to this team, he has performed very well for us so far and is going to do the same again next season."