Gianni Paladini has hit back at Peter Pannu after the Birmingham City chairman implied the Italian's consortium does not have enough money to buy the club.
Paladini's group - who planned a swift move into St Andrew's - said they tabled an offer worth around ?30million which was dismissed by Pannu who is in control of negotiations.
And Paladini, after hearing the Hong Kong businesman's rant, challenged the Blues acting chairman to let them prove themselves.
"Mr Pannu has insulted me and our backers by saying we don't have the money," said Paladini.
"Now, prove me wrong, Mr Pannu, by providing us exclusivity for two weeks to finalise the deal at the original price that was offered - and agreed.
"If we are unable to do so, you can then show I am wrong."
Pannu previously told the Hong Kong media: "If people don't have the money, they should just shut up.
''I support freedom of speech and he [Paladini] can say what he likes in the press, but if anyone wants to buy our club they better prove they've got the money to do it before they talk to the British media.
"There's been a complete misrepresentation that he's closing in on a purchase and it's totally without foundation.
''We need to put a stop to this nonsense. He's just trying to get the club on the cheap."
The 23-year-old, who has scored three times in six appearances since returning from a knee injury, was replaced by Richie Ryan after 71 minutes of Saturday's 2-1 win at Ross County.
The former Liverpool trainee, signed for United from Airdrie, is now set to be out until the turn of the year.
Speaking ahead of Tuesday night's Scottish Premier League clash with Motherwell at Tannadice, Houston said: "At the time he didn't know it was broken, his hands were so cold.
"He knew he was hurt and he came off. We took him to the hospital as soon as we got back to Dundee and unfortunately he's got two wee broken bits in his hand.
"He's going to be out for a minimum of four, maximum of six weeks. It's a blow for us and a blow for the boy because he's just come back from a knee operation.
"It's not been a great start to the season for him. These things happen sometimes in football."
An FA spokesman said it was "likely" that the governing body would launch a formal investigation once the match officials' reports had been received.
On Sunday, some Hammers fans appeared to mock the gassing of Jews in the Holocaust as Spurs supporters were allegedly subjected to a second dose of anti-Semitic abuse in the space of four days.
Just a matter of days after Ashley Mills was stabbed before Thursday's Europa League game in Rome, West Ham supporters sang 'Viva Lazio', 'Can we stab you every week?' and hissed on several occasions, apparently mocking the mass execution of Jews during the Second World War.
There were also reportedly chants about Adolf Hitler during the match, which Spurs won 3-1.
West Ham released a statement in relation to Sunday's chanting. A statement on their website on Monday morning read: "West Ham United are in contact with Tottenham Hotspur to assist them with their investigation into the conduct of a small number of supporters and alleged inappropriate chanting during yesterday's match at White Hart Lane.
"West Ham United will take the strongest possible action against any of their supporters, including enforcing life bans from the club, that are found guilty of behaviour which is categorically not condoned by West Ham United.
"During the 46 games in the Championship last season, West Ham United had zero arrests for racism or violence, so while we are surprised to see such reports today, we will examine any available evidence of such conduct thoroughly and take the appropriate action."
At his post-match press conference, West Ham manager Sam Allardyce insisted he did not hear the chants.
"I didn't hear it," Allardyce said.
"I don't hear what the fans say or do when I'm concentrating as a manager on a game of football.
"They shouldn't be doing things like that, it is the least of my worries at the minute isn't it?
"What do you want me to say? If I didn't hear it, I can't condemn it can I?
"I will wait and look at it myself and make a comment once I have listened to what they have said.
"I don't want to be a political animal, I'm here to talk about football and not what fans are saying and singing."
