Gary Neville has slammed the Glazers and the bidding process to take over Manchester United.

Sportsmail revealed on Tuesday evening how a third – and final – round of bidding for United is set to take place, with best offers to land before the end of the month, despite two previous rounds of offers.

However, in a significant shift forwards in what has been a long-running saga since the club’s unpopular American owners put the club up for sale in November, those still in the battle – who include Qatar-based Sheikh Jassim bin Hamad al-Thani and British billionaire Sir Jim Ratcliffe – have been told that there are now two deadlines.

The first, which is in the middle of next week, is related to due diligence. The second – April 28 – is for final bids to drop. It can also be disclosed that there is a growing belief among those close to the process that the Glazers, are seeking a full sale of the club rather than partial investment.

However, the news of another round of bidding infuriated United legend Neville, who urged the Americans to get out of the club as soon as possible.

He tweeted: ‘They’re making it up as they go along! Shoddy way to run a sale process. They need to get out by end of May to allow the new owner a fighting chance to impact the next transfer window and get moving!’

Neville continued: ‘Taking it to a 3rd round (of bidding) is just classless. The market has obviously not given them the answer they want! It’s like they’ve made a pact to each other that they won’t go for less than £1bn each family member. (5 of them). If they stay in after all this it will be toxic!’

The Glazers have have been a source of contention at Old Trafford ever since they became majority owners in 2005, facing significant fan anger and backlash. After taking over the club through a leveraged buyout which placed £525million worth of loans onto the brand of United, they have racked up the club’s debts to £536m.

Overall, the Glazers have taken more than £1bn out of United in the form of dividends, interests, costs and fees during their 18-year-reign, which has been dominated by a decline in on-pitch performance and success.

When announcing the club was up for sale in November, they invited bids for control and for a stake in exchange for a cash injection but the noises so far are that a complete takeover is looking likely. That said, partial investors remain in the process.

Raine Group, the New York based bank overseeing the sale, declined to comment, as did spokespeople for Sheikh Jassim and Ratcliffe.

Reports in the US earlier on Tuesday claimed that there are seven prospective ownership groups which have received feedback from Raine, although there is scepticism in some quarters over whether that is the case.

The decision to move to a final round, rather than enter into a period of exclusivity with one group, may suggest that the Glazers have not yet attracted a price at which they are happy to sell.

As per Neville’s point, it also means that things will have to progress rapidly for a new owner be in place for the forthcoming transfer window with Erik ten Hag likely to be desperate to strengthen his squad after a promising first season at the club.

Second offers were made on March 23 by Ratcliffe’s group and a day later by Sheikh Jassim. Both were given extended deadlines to place their bids.

Aside from two known bids for full control, there are offers from a number of groups to take a partial stake in the Premier League giants.

Such a move would allow the Glazers to stay in charge and provide the funds necessary to upgrade Old Trafford or build a new stadium and refurbish the club’s training ground.

However, it would not be popular with wide sections of United’s fanbase.