"It can only be done if we have the support from other businessmen within Leeds," said former Huddersfield chairman Fisher.
"Nobody's in a position to throw millions of pounds at this. There's no one benefactor like Roman Abramovich."
Fisher's consortium is currently one of two interested in saving United.
Bolton director Ian Currie and ex-Leeds player Trevor Cherry are the other members of the group.
Fisher was called in by Zeus Capital, the corporate finance experts who are putting together a rescue package.
Richard Hughes, co-founder and a director of Zeus Capital, said: "We are getting on with the work.
"We know it's in our interests to put something to the creditors sooner rather than later, but we are delighted with the way things are progressing."