The Manchester United Supporters' Trust says the 2 bids made for the nine person raised questions astir sporting integrity, indebtedness levels and inclusivity.
British billionaire Sir Jim Ratcliffe and his petrochemicals steadfast Ineos person bid for "majority ownership".
Sheikh Jassim bin Hamad Al Thani, president of 1 of Qatar's biggest banks, has besides tabled a bid.
MUST has a "clear list" of demands for owners, but adhd "further considerations arise" with the 2 authoritative bids.
The Glazer family, who person owned United since 2005, are considering selling the nine and a 'soft deadline' of Friday was acceptable for proposals.
The American owners confirmed they wanted to "explore strategical alternatives" for the club.
MUST says they privation a caller proprietor to put successful the team, wider club, Old Trafford and "ensure fiscal stability", adding these principles person been backed by 150 Manchester United instrumentality groups from crossed the world.
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Ineos said it wants to marque the 20-time English champions a "beacon for a modern, progressive, fan-centred attack to ownership".
The Ineos group, owned by 70-year-old British billionaire Ratcliffe, has a past of concern successful athletics and owns French Ligue 1 nine Nice and Swiss Super League nine Lausanne.
Described arsenic a life-long Manchester United fan, Sheikh Jassim is president of Qatari slope QIB and the lad of a erstwhile premier curate of Qatar.
Paris St-Germain president Nasser al-Khelaifi is acceptable to beryllium a cardinal fig successful immoderate Qatari ownership bid, adjacent if helium could person nary nonstop engagement successful the club.
The imaginable of Qatari concern successful a Premier League nine - and 2 large European teams being owned by the Gulf state - has raised concerns among quality rights and LGBTQ+ groups.
"There are questions astir sporting integrity fixed the exceptionally adjacent links betwixt immoderate bidders and the owners of different European clubs including PSG and Nice," said MUST, which is 1 of the largest supporters' groups successful the satellite with implicit 200,000 members.
"There are besides questions astir whether immoderate bids volition besides beryllium based connected precocious levels of debt.
"We besides enactment the value that immoderate proprietor respects the rights of each people, peculiarly women and the LGBTQ+ community. Concerns person been raised by different fans groups which we afloat support."
Qatar Sports Investment (QSI), headed by Al-Khelaifi, had been looking astatine the imaginable for taking a smaller involvement successful a Premier League club.
However, due to the fact that of Uefa rules that forestall prevent multi-club ownership, immoderate Qatari bid to bargain United successful its entirety would person to travel done backstage individuals oregon a antithetic organisation.
There are besides expected to beryllium astatine slightest 2 offers for United from the United States, portion determination person been suggestions of involvement from Saudi Arabia.
That means determination could beryllium up to 5 parties trying to negociate a afloat sale, with others looking to marque a smaller concern successful instrumentality for a partial involvement successful the Old Trafford club.
"We impulse each bidders to unfastened a dialog with fans groups alongside the bidding process with the club, successful bid to sermon their proposals including the supra issues," added MUST.
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