Manchester Utd have ended talks with the US sports tycoon Malcolm Glazer over a possible takeover.
Malcolm Glazer already owns 28.1% of Man Utd
United said Mr Glazer's proposed move was "not in the best interests" of the club because it relied too much on borrowed money.
However, United added they intended to have further talks with Mr Glazer and other shareholders about the club's future "in due course".
Mr Glazer has recently increased his stake in the club to 28.1%.
If he increased his stake to the 30% level he would be forced to make a formal takeover offer.
Shares in Manchester United finished the day down six pence at 277.75p.
"We looked at the proposal but a key aspect of it was the level of debt," the club's chief executive David Gill told MUTV.
"That, coupled with their overall business plan meant it was an unattractive proposal."
United issued a statement earlier on Monday.
"The financial returns in any football club are very closely correlated with performance on the pitch," it said.
The club said that it considered its current financial structure was "appropriate" and gave it a "distinct competitive advantage to pursue commercial opportunities as they arise and invest to sustain the playing success".
"The board has decided to inform all shareholders that it would regard an offer which it believes to be overly leveraged as not being in the best interests of the company," the club said.
"Accordingly the board has determined that it would not support any offer underpinned by the structure which has been outlined in relation to the Glazer
family's potential offer.
"The board has informed the Glazer family of these views and that it has therefore terminated discussions with respect to the current proposals."
Mr Glazer has upped his stake in United significantly in the past couple of weeks.
His increased investment followed the breakdown of talks between him and the Irish racing millionaires JP McManus and John Magnier who own a 28.89% stake in the club.
United said that they intended "to have further discussions with the Glazer family and other interested shareholders in order to seek to develop a long term solution that brings stability to the company's ownership structure".
The end of negotiations between Man Utd and the Glazer camp was welcomed by fans, who have been campaigning against the takeover.
"It is fantastic news and due in no small part to the campaign we have waged against him (Mr Glazer)," said Oliver Houston, spokesman for Shareholders United.