The Barcelona midfielder emerged as a top target for United last summer, with David Moyes eager to add proven Premier League experience to his ranks.
Fabregas made it clear, though, that he had no intention of leaving the Nou Camp at that time.
His stance has not changed, with the former Arsenal man having worked hard to secure a return to his home-town club in 2011.
There have, however, been reports that Barca may be prepared to offload the Spain international as they look to rebuild in the wake of a trophyless campaign.
Were the door to be opened to a big-money transfer, United goalkeeper De Gea hopes United and new boss Louis van Gaal can be at the front of the queue looking to get a deal over the line.
He told La Sexta while on pre-World Cup duty with the Spanish national side: "I'm trying to convince Cesc that he should come to United.
"But it's hard because he is doing well at Barca and it's his home."