The club's supporters' association hopes to persuade Trade Secretary Peter Mandelson to refer the deal to the Monopolies and Mergers Commission.

Mr Mandelson could take the decision as early as next week - after receiving a report from the Office of Fair Trading - making what will be one of his trickiest choices since taking the job.

Nigel Hawkins, football analyst, says it is "odds against a referral to the Monopolies and Mergers Commission"

Supporters' spokesman Lee Hodgkiss described himself as "delighted" at the news that Rupert Murdoch's company has so far managed to purchase only 45% of the football team's shares.

The club's fans are overwhelmingly opposed to Murdoch ownership

"I'm sure Rupert Murdoch is pretty disappointed," he told BBC News Online. "Seventy-five per cent [of shareholders] have decided not to sell their shares to him."

Mr Hodgkiss said the meeting of supporters and MPs in Parliament marked a new phase in the campaign to keep BSkyB out the Old Trafford boardroom.

"We're here today to try to win over the floating voter really, the people who are not really sure yet what the best way to go is.

"We would hope that they would use their influence to talk to Mr Mandelson and get over to him our concerns. People within football are totally against this.

"We've made it clear from the start this isn't just an issue for Manchester United, it's an issue for the footballing community at large. We've got representation from other clubs around the country."

David Beckham: Star player

Mr Hodgkiss dismissed the suggestion that fans from other clubs had more to fear from the injection of Mr Murdoch's millions into Manchester United.

He asked: "Is it in Murdoch's interest for Manchester United to remain the greatest football team in the world?

"He's said he doesn't want a situation for the Premier League like in Scotland where Rangers tend to win every year.

"Well, I'm a Manchester United supporter. I want my team to win every single year. I know they won't and that's what makes it exciting. But it's not in Murdoch's interests to make Manchester United as successful as we want them to be.

"The main crux of our position is that we lose the independence of our football club. Some people say, 'You're a plc now'. That's correct but the money that the club makes now is poured back in to the business.

Peter Mandelson: Could take the decision of referral next week

Manchester United Supporters' Association has already written to every MP and has received overwhelming support from about 100.

About half that number have signed an Early Day Motion registering their opposition to the deal.

The EDM states the purchase "will create an unacceptable situation" and "is not in the best interests of fans, clubs or television viewers and the sport in general".

One of the motions supporters, Conservative MP Nigel Evans, said: "We're putting pressure on the DTI to ensure it does get referred. That's as much as we can do. We're hoping the DTI will move on this and protect the sport for the fans."

Labour MP Joe Ashton, who is co-ordinating efforts to block the take-over, said he had not many anyone in Parliament who supported the deal.

"We're trying to get a debate Commons next week on the floor of the House. We're very hopeful that might happen."

Rupert Murdoch: Potential owner

The supporters' association is optimistic this could translate into the bid being referred for further inspection.

"We set out to achieve certain things," Mr Hodgkiss said. "We set out to achieve a delay, for the Office of Fair Trading to delay their decision. We achieved that.

"The next step is to get this referred to the Monopolies Commission and that's what this is all about.