New United manager David Moyes revealed on Friday that the Old Trafford club had submitted a bid for the Spain international as he looks to strengthen his squad.
However, Bartomeu has ruled out a move for the former Arsenal captain, insisting the midfielder is not available for transfer.
"Cesc will be staying," the senior Camp Nou official told AS.
"The club will not sit down to negotiate his sale with anyone."
The news is a further blow to Moyes, who has already missed out on one midfield target after Thiago Alcantara left Barcelona for Bayern Munich.
Fabregas rejoined the La Liga champions in 2011 after leaving the club for Arsenal eight years earlier.
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