The Union of Fans, an umbrella group comprising six supporters organisations, has savaged the club board in an incendiary statement.
They claimed the failure to offer legally-binding assurances over the stadium and training ground underlines "how much danger our vital assets are in".
And the union have also accused major shareholder Sandy Easdale of wielding even greater power at Ibrox than chief executive Graham Wallace.
The latest, and by far the most scathing, broadside at those in power at the troubled Glasgow giants came in response to a statement the club issued on Saturday night.
The union described the club's account of a meeting that took place at Ibrox last Wednesday night as "a deliberate misrepresentation of the facts". They stated they had been offered legally-binding assurances over Ibrox after meeting with non-executive director Norman Crighton, Easdale and Wallace. The Union also stressed they had asked for the same guarantees to be given over the multi-million pound training complex at Auchenhowie.
But no contact has been made since then and the board statement referred only to a "commitment" not to sell and leaseback or grant security over Ibrox.
The Union of Fans have claimed that this shows the "grave danger" that both Ibrox and Murray Park are under.
Their statement read: "Since that meeting we have heard nothing from the board.
"It is clear that they have now rejected Mr Wallace's proposal to give a binding under-taking over Ibrox.
"It is clear that they have considered our proposal that the same undertaking be given for Murray Park and they have also rejected that.
"The idea that this latest board proclamation should give supporters any type of additional confidence over the club's assets is therefore utterly ridiculous.
"In fact, it should confirm just how much danger our vital assets are in.
"They told us we would receive a swift response following their deliberations. We have received no response. It is clearly impossible to deal with this board in good faith."
The statement also claimed that Easdale's "associates" - he holds the proxies for Blue Pitch and Margarita Holdings - are set to benefit from future financial transactions.
And the group that has set up Ibrox 1972 Ltd has urged supporters to "think carefully" about renewing season tickets with the current board in charge.
The statement went on: "They told us that over the past two weeks, all major investors, bar one, have indicated they will participate fully and proportionately in any future rights issue.
"We do not believe this to be the case. They told us that all those major investors are supportive of their business plan and were impressed with the 120-day review. We do not believe this to be true.
"They told us that they have access to an instant £5million of equity funding from existing major investors.
"This, according to Mr Wallace, is available at 'the push of a button'. "We believe that, if this is true, it will be used to benefit Mr Easdale's associates.
"It is clear that Mr Wallace, despite being chief executive, has less influence in the PLC boardroom than Sandy Easdale, who is not even a member of the PLC board.
"It is clear that Murray Park is in grave danger and has been since December 2013. The statement from the board that they 'will not be seeking' a sale and leaseback of Ibrox is not binding and it is still not unequivocal.
"We believe, as long as the shareholders fronted by Mr Easdale are calling the shots in the boardroom, Ibrox will remain in grave danger too.
"Until this situation is resolved we would continue to urge supporters to think very carefully before they hand this board their hard earned money up front.
"It is clear from meagre renewal levels that a large majority of fans do not trust this board. Our experience is that this position is the correct one to adopt. Support the team, not the regime."