Manchester United fans will oppose any takeover bid for the club unless they are involved and aim to raise their shareholding to more than 25 percent, a leading supporters' group says.

"We are against the ownership by a single company or individual whose main motive is profit," Nick Towle, chairman of Shareholders United, told Reuters.

On Monday, the eight-times English Premier League champions said they had called off talks with U.S. sports tycoon Malcolm Glazer about his proposed offer for United but did not rule out further discussions.

Debt-free United said in a statement that they did not support a capital structure for an offer with a high level of debt. Towle echoed those sentiments.

"If he (Glazer) wants to borrow large amounts of money, then the repayments would be from our profits," he said. "This is a risky financial model and could be a disaster."

Thousands of fans opposed the Glazer bid, many of them carrying banners during the 2-0 win over champions Arsenal at Old Trafford on Sunday saying United was not for sale.

Glazer, owner of American football team Tampa Bay Buccaneers, has 28.11 percent of the club's shares. Irish racing tycoons John Magnier and J. P. McManus own 28.9 percent.

Towle, whose group also opposed the 1999 takeover bid by satellite television company BSkyB, said his group's target was to increase the individual shareholders' stake in the club to more than 25 percent from 18 percent.

"Our doors are open to anyone who can help us reach this objective. We need this power to be able to influence decisions," he said.

"Fans are the emotional and financial stakeholders in the club. We pay for the tickets and television subscription...We should be recognised."