Thomas Zilliacus says his second offer for Manchester United still stands - despite declining to enter into a third round of negotiations.
The Glazer family is in the process of potentially selling the Premier League giants - and recently entered a new round of bidding after two previous windows.
The 69-year-old Finnish businessman had previously said it was a 'farce' that the Glazer family had entered a third stage, and had no plans to submit another entry.
But Zilliacus told the BBC's How To Buy A Football Club podcast that despite no desire to enter a third offer, his second bid still stands if the Glazers are willing to consider it.
Zilliacus told the BBC: 'My earlier offer still stands and I am willing to pay a premium above what I offered.
'I'm not going to be participating in a third round because I find it highly unprofessional. I see no reason whatsoever why a third round is basically starting the whole thing from scratch.
'It seems odd to me that, if there is a genuine will to sell and you have three serious bidders, why you don't sit down with the bidders, discuss and negotiate and hopefully come to a number that everyone can agree.'
There are now two deadlines - one next week, which relates to due diligence, and the final bid deadline of April 28.
Jim Ratcliffe, Britain's richest man, and a Qatari consortium led by Sheikh Jassim bin Hamad al-Thani were the other public bidders for Manchester United.
The Finn also called on the Glazer family to 'put a price tag' on the Red Devils.
The Glazers bought the club for £790m in 2005, and were thought to be seeking a sale price of around £6billion - but the uncertainty around the exact figure has led to additional confusion.
The Finn planned to make his purchase through XXI Century Capital, an investment firm owned by his holding company.
Zilliacus says the protracted nature of the proposed sale will hamper Erik ten Hag's ability to buy new players in the transfer window, an issue raised by the Manchester United Supporters Trust.
The entrepreneur told the BBC: 'I can't see the Glazers spending a lot of money on new players. If they have decided to sell the club, why would they do that?
'The potential to have a negative impact on the club is big and is growing every day when there is no decision on this.'
The club's world-famous Old Trafford home was omitted from the list of 10 stadiums that formed the UK and Ireland's bid for Euro 2028.
Zilliacus was surprised to see the Theatre of Dreams left out of the tournament plans due to a lack of certainty over whether the stadium would be up to scratch for the elite tournament.
Liverpool's Anfield Stadium was also overlooked in favour of neighbouring Everton's new ground.
'Most people know the name of three stadiums in England - Old Trafford, Wembley and Anfield,' Zilliacus said.
'You could travel just to see those stadiums. It is a real shame if Old Trafford is in a condition where it cannot be included.'
Manchester United follow Thursday's 2-2 draw in the Europa League against Sevilla with a Premier League trip to Nottingham Forest on Sunday afternoon.