The Ineos billionaire Sir Jim Ratcliffe remains the leading candidate to buy Manchester United Football Club despite an inconclusive board meeting held late last week.

Sky News understands that directors of the Premier League club’s holding company met on Thursday to discuss the progress of its £5bn-plus auction.

Controlled by members of the Glazer family but also comprising a number of independent directors, the board was updated on the sale process by Raine, the merchant bank advising Manchester United.

A source close to the auction said the directors did not opt to enter into exclusive negotiations with either Ineos Sports or its principal rival, the Qatari businessman Sheikh Jassim bin Hamad al Thani.

Sir Jim is proposing to buy a majority stake in the Red Devils which would leave two of the Glazers involved, while Sheikh Jassim wants to buy the club outright.

The source said that Ineos remained the “leading” bidder despite a further, improved offer from the Nine Two Foundation – Sheikh Jassim’s bid vehicle – earlier this month.

Nevertheless, a further proposal remains possible, with a signed deal with either bidder said to be unlikely prior to United’s FA Cup Final against local rivals Manchester City next weekend.

Sir Jim’s takeover proposal includes ‘put and call’ arrangements that would allow him to buy the Glazers’ remaining shares after three years.

Ineos’s bid is said to value the whole of United at somewhere between £5bn and £5.5bn.

The Glazers have owned Manchester United since buying it for just under £800m in 2005 – an 18-year tenure marked by protests and a conspicuous dearth of trophies since the retirement of Sir Alex Ferguson, its former manager.

The Red Devils did win their first trophy for six years by beating Newcastle United in this season’s Carabao Cup Final.

In addition to the two proposals which would trigger a change of control, the Glazers have also received at least four credible offers for minority stakes or financing investment in the club.

These include an offer from the giant American financial investor Carlyle, Elliott Management, the American hedge fund which until recently owned AC Milan, and Sixth Street, which recently bought a 25% stake in the long-term La Liga broadcasting rights to FC Barcelona.

These investors’ proposals would provide capital to allow United to revamp the ageing infrastructure of its Old Trafford home and Carrington training ground.

Sky News exclusively revealed last November the Glazer family’s plan to explore a strategic review of the club its members have controlled since 2005, kicking off a six-month battle to buy it.

At a valuation of £5bn or more – which is below the Glazers’ rumoured asking price – a sale of Manchester United would become the biggest sports club deal in history.

Part of the justification for such a valuation resides in potential future control of the club’s lucrative broadcast rights, according to bankers, alongside a belief that arguably the world’s most famous sports brand can be commercially exploited more effectively.

United’s New York-listed shares have gyrated wildly during the process amid mixed views about whether a sale of the club is likely.

On Friday, they closed down at $18.97, giving the club a market valuation of just under $3.1bn.

Fury at its participation in the ill-fated European Super League crystallised supporters’ desire for new owners to replace the Glazers, although any sale to state-affiliated Middle Eastern investors would – like Newcastle United’s Saudi-led takeover – not be without controversy.

Confirming the launch of the strategic review in November, Avram and Joel Glazer said: “The strength of Manchester United rests on the passion and loyalty of our global community of 1.1bn fans and followers.

“We will evaluate all options to ensure that we best serve our fans and that Manchester United maximizes the significant growth opportunities available to the club today and in the future.”

The Glazers listed a minority stake in the company in New York in 2012 but retained overwhelming control through a dual-class share structure which means they hold almost all voting rights.

A Manchester United spokesman declined to confirm that a board meeting had taken place.