Rooney was the Blues' primary transfer target in the close season and they had two bids for the 27-year-old turned down.
The striker has since become only the fourth United player to reach 200 goals for the club and although Rooney is yet to commit to an extension to a contract that finishes in 2015, a departure to another English club seems highly unlikely.
"We are not in the business of strengthening our key competitors in England," Gill, who is a United director after stepping down from UEFA's executive committee, told BBC radio.
"You have to see our response when Gabriel Heinze wanted to join Liverpool (in 2007).
"We went to a Premier League arbitration panel to show that we didn't commit to him moving within England for a certain sum of money.
"We wanted to keep (Rooney) in any event and not sell him overseas. You don't win football matches with money in the bank.
"You want players on the pitch. Wayne Rooney has been, and will continue to be I am sure, a great player for Manchester United."
It has been suggested that United may look to reduce Rooney's reported £250,000 a week contract when negotiations between the two parties begin, a proposal which would be unacceptable to the England frontman.
Gill is slightly detached from such proceedings now but he does feels talks are bound to start at some point.
"Yes, I am sure they will look at it," said Gill.
"We have an approach to dealing with players' contracts at Manchester United that has stood us in good stead for many years.
"I am sure (executive vice-chairman) Ed (Woodward), (manager) David (Moyes) and the owners will continue with that policy."