“I don’t think players should feel pressured by clubs, particularly the bigger clubs, to take pay cuts,” added the former Ireland midfielder, who left United in 2005 in strained circumstances.
Keane said a player’s individual contract was a personal matter between him and the club and it was nonsense to suggest all should do the same.
He added that it was always made clear to him when negotiating deals that it was a business.
“When the clubs with billionaire owners in the background come to the players and say they are in trouble – no, no, you honour the contract,” he said.
“This idea that we should be getting players to give up their wages at these big clubs, forget about it because these clubs are the first to tell you, ‘This is a business, lads, this is how it works’.”
Former United and England defender Gary Neville repeated a call for the Premier League to come up with a package to help clubs in the lower divisions survive.
“I’ve gone from opportunity, to despair, to almost now pleading with somebody at the Premier League just to do the right thing for the game,” he said.
“Why am I on calls with chairmen and owners of EFL League Two (fourth-tier) clubs who are desperate, who don’t know how to pay their next wages, they are worried the clubs are going to go bust for the sake of a few million pounds?”