"The board of Manchester United confirms that at a shareholder meeting Glazer has indicated, on a very preliminary basis, potential revisions to its previous proposal," a statement to the London Stock Exchange said.

"The board does not intend to open discussions on this matter unless it receives a definitive proposal from Glazer," the statement added.

Manchester United ended talks with Glazer in October over his possible takeover, saying his bid risked leaving the club mired in debt.

Glazer and his family have built up a stake of 28.1 percent in Manchester United, the world's richest football club, but have not yet put a formal offer on the table.

The tycoon caused a stir recently by ousting three members of the board at United's annual general meeting, causing bankers JP Morgan to pull out of plans to financially support Glazer's bid.

The owner of NFL franchise Tampa Bay Buccaneers could however now be ready to raise the funds to complete a hostile 800 million-pound bid, despite deep opposition from the club's fans.