Celtic boss Ronny Deila says keeping his best players will take priority over acquisitions in the transfer window.
Chelsea striker Fernando Torres is understood to be set for a return to Atletico Madrid, according to Sky sources.
Ferdinand, who has spent over a decade at United under Sir Alex Ferguson, has not yet agreed an extension on his current deal that runs out this summer.
And the 34-year-old, who won his sixth Premier League title this season, announced on Wednesday he was retiring from England duty in order to concentrate on club matters.
And United boss Ferguson said: "I think it is something he could have done last year.
"Ending his international career will definitely help him, as it did with Paul Scholes, and hopefully Manchester United will get the benefit of that."