United have been criticised for failing to seize the option of buying Tevez for £25million in 2009 after he had spent two seasons on loan at the club.
Tevez joined rivals Manchester City instead and has become a cult hero with the Blues.
But Fergie told the Sunday Mirror: “Tevez told us he was only going to play for four more years.
“If we had signed him on a five-year contract knowing that he was going to quit in four, there would have been no re-sale value for us.
“I’m not sure Inter would pay £45m, especially after he’s said he wants to go back to Argentina to see his kids. I can see him staying at City.”