Manchester United have reportedly opened talks with Qatari investors as speculation intensifies over the future ownership of the Premier League giants ahead of a deadline for bids.

The American Glazer family, who completed their takeover of the 20-times English champions in 2005, announced in November that they were open to a sale or investment.

British billionaire Jim Ratcliffe's Ineos company officially joined the race to buy the club last month - the only bidder to publicly declare an interest so far.

Potential buyers are understood to have until February 17 to table offers.

The Daily Mail said a group of private investors from Qatar want to buy United and talks have taken place with the club's hierarchy, confident that theirs would be the strongest bid.

The Guardian reported that Qatar's ruler, Sheikh Tamim bin Hamad Al-Thani, was interested in buying United, just weeks after the energy-rich Gulf state hosted the World Cup.

But the emir bought French champions Paris Saint-Germain in 2011 through Qatar Sports Investments (QSI) - meaning a full buyout of United would not be permitted under current UEFA regulations.

Britain's Press Association said QSI was considering the purchase of a minority stake in United or another Premier League club.

The organisation is a subsidiary of the Qatar Investment Authority (QIA), the country's sovereign wealth fund, which has assets worth hundreds of billions of dollars.

The chief executive of the QIA, Mansoor Al-Mahmoud, told Bloomberg last month: "Sovereign wealth funds are becoming investors in some of the clubs and you will not be surprised if we invest in this (area) but again we go into a very fundamental process and making sure if we invest this is very commercially driven for our future generations."

Amnesty International said Qatari interest in United should act as a "wake-up call" to the Premier League over its ownership rules.

"Coming in the wake of the World Cup and strenuous efforts from the Qatari government to fashion a glitzy new image for the country, it seems highly likely that any Qatari bid for Manchester United would be a continuation of this state-backed sportswashing project," said Peter Frankental, Amnesty UK's economic affairs director.

He added: "We're not necessarily opposed to the involvement of state-linked overseas financial consortia in English football, but the Premier League must urgently strengthen ownership rules to ensure they're human rights-compliant and not an opportunity for more sportswashing."

The unpopular Glazers saddled United with huge debts and further angered fans by backing the failed European Super League project in 2021.

The club have not won the Premier League since 2013 and have failed to win any silverware since 2017.

United are third in the Premier League this season after an improvement in form under manager Erik ten Hag, who took over before the start of the current campaign.