Sheikh Jassim Bin Hamad Al Thani will make his second bid for Manchester United on Wednesday evening.
Sources in the US say talks last Thursday in Manchester between Sheikh Jassim's Qatari delegation and United executives were positive.
His advisers are now working on putting together a new bid which is expected to be submitted by close of business on Wednesday.
There is also growing confidence among bidders that the Glazer family, who believe the club is worth at least £6bn, are willing to sell United.
It was previously understood that the Qatari bidders were determined not to pay over the odds for the club, but that stance has softened in recent days coinciding with a delegation's visit to Old Trafford.
A Qatari delegation travelled to Manchester from London by train and received a warm welcome. Talks were held across 10 hours - a lot longer than expected.
Sheikh Jassim and members of his team had been to Old Trafford as fans before, and the focus of this visit was to get a perspective on what they could do with their capital investment regarding infrastructure, youth development and the women's team.
They had been trying to get a better understanding before they make another bid. It was too early for Sheikh Jassim to be there in person and he did not just want to go for a photo opportunity.
He sent his top team of experts in finance, banking, property and law with the Qataris totally committed and in this to buy the club.
Sky Sports News has been told by sources in New York that "there should be no doubt at all that Sheikh Jassim wants to be the owner and custodian of United".
Ratcliffe expected to make second Man Utd offer
British billionaire Sir Jim Ratcliffe is also expected to make a second offer for Manchester United next week after visiting the club on Friday.
The INEOS delegation spent six hours at Old Trafford and Carrington with meetings finishing at about 4pm.
Ratcliffe and INEOS are making no comment, and they will now go away and digest the information they received on Friday before making a new formal offer.
Ratcliffe, 70, flew in from Nice on Thursday and visited United's management team at Old Trafford on Friday, alongside INEOS sport representatives.
He was photographed outside Old Trafford after meeting club executives - unlike Sheikh Jassim, who did not visit Manchester personally the previous day.
Sky Sports News chief reporter Kaveh Solhekol said: "It's an interesting contrast with Sheikh Jassim. Sir Jim was happy to be filmed and photographed, and it was significant that [Man Utd CEO] Richard Arnold was there to greet him when he arrived, shaking his hand and being photographed then too.
"It gives you another sense that maybe the Glazers are serious about selling Man Utd.
"This was a high-powered delegation from INEOS, he was there with the two co-owners, Andy Currie and John Reece. Sir Dave Brailsford, who used to be the director of cycling at Team Sky - he's now INEOS' director of sport and he was there too."
Aaron Ramsey has described prospective Manchester United owner Sir Jim Ratcliffe as "very passionate" in his desire to take his Nice team "all the way to the top".
Ramsey joined Nice - who the INEOS owner also runs - on a free transfer last summer.
"The owner is very passionate and very invested into Nice. He wants to take Nice all the way to the top," new Wales captain Ramsey said at a press conference before opening Euro 2024 qualifiers against Croatia and Latvia.
Elliott Investment Management has also made it through to the second stage of the process, although the firm is said to be offering funding rather than a takeover.