Sources have told BBC Sport a fresh bid was submitted on Tuesday morning amid further talks involving the Raine Group, who are handling the sale.
The Qatari banker and Sir Jim Ratcliffe’s Ineos Group are the two main parties looking to buy the Old Trafford club.
Both groups submitted third bids at the end of April
It is understood the new bid is for 100% of the club, will clear United’s debt and includes a separate fund directed solely at the club and local community.
Figures in March showed United owed £969.6m through a combination of gross debt, bank borrowings and outstanding transfer fees with associated payments.
The Glazer family announced in November they were considering selling Manchester United as they “explore strategic alternatives”.
Although there has been no response from the Glazer family since the last bid deadline on 28 April, there has been increasing confidence in the Ineos camp that their efforts to buy United would be successful.
It is understood one of Ratcliffe’s suggestions has been to lower the amount of United he wanted to buy from an initial 69% for all the Glazer stake to just over 50%, which would allow co-chairmen Joel and Avram Glazer to retain some involvement.
Avram Glazer followed up his appearance at the Carabao Cup final in February by watching United’s women’s team lose in the FA Cup final against Chelsea at Wembley on Sunday.
Glazer subsequently visited a London hotel owned by Sheikh Jassim’s father, sparking more rumours about the sales process, although BBC Sport has been told there were no talks held involving the Raine Group.
There has been no indication when the Glazer family will make a decision over the future direction of United.
They bought the club for £790m in 2005 and have established a valuation of between £5bn and £6bn for it.
It had been felt an announcement could come this week given the transfer window opens in less than a month, which would give manager Erik ten Hag some clarity over his summer budget.
However, there is no guarantee this will happen.-BBC