Owner Craig Whyte has told Rangers supporters that their annual meeting has been delayed because of their ongoing tax case.
Rangers Supporters Trust urged the club chairman to set a date amid growing fears about the club's finances.
A Trust statement said: "Mr Whyte has stated that the AGM can't take place until the club accounts are signed off.
"And that challenges around the potential tax case liabilities mean these continue to be worked on."
The Scottish champions are waiting on a tax tribunal verdict concerning payments made to staff in benefit trusts before Whyte bought out Sir David Murray in May.
That case could cost the Scottish champions up to £49m and Whyte this week admitted borrowing money on the strength of future season-ticket sales to help the club's cash flow.
"He further stated that as soon as the accounts are signed off an AGM will be called," said the Trust.
"Finally, the chairman stated that he had an open door to the RST to speak on any issues of concern to our members."
Trading in shares in Rangers was suspended last month after a delay in publishing the club's audited accounts.
Whyte this week denied claims he had used a loan secured on future ticket sales to facilitate last year's takeover, which involved paying off a debt of £18m to Lloyds Banking Group.
However, in a statement released on the club's official website, the Rangers chairman did admit to borrowing money from Ticketus - a London-based group that allows clubs to borrow money on the strength of future season-ticket sales.
Former Rangers chairman Alastair Johnston, who was opposed to Whyte's takeover, questioned the long-term use of Ticketus and urged the Motherwell-born businessman to explain exactly how he has spent advance season-ticket revenues.
RST chairman Gordon Dinnie contacted Whyte urging him to "publicly clarify the situation both for our members as shareholders and the wider Rangers support".
"Supporters are rightly concerned about the club's financial future with the verdict of the tax case just around the corner and reports of season-ticket revenue being re-mortgaged for the next four years will only heighten fears," said Dinnie.
"Supporters have been aware in the past of how Ticketus was used to borrow money against Champions League income which would come into the club later in the season, but borrowing on season-ticket money over four years seems to see the club enter dangerous and unchartered waters."
The supporters' body urged Whyte to quickly set a date for the annual meeting "and retaining a properly liquid public market in the shares of the company with the same standard of accounting information which has previously been available to shareholders".
"We would rather concentrate on cheering on the team, but recent developments like failing to get accounts signed off, not holding an AGM and now this new debt all raise serious questions," added Dinnie.
"We are aware, as is every Rangers fan, that the outstanding HMRC case has severely inhibited the manner in which the club has been able to operate.
"Coverage of this issue has been predominantly speculative, frequently prejudiced and occasionally hysterical and whilst the RST appreciates the robust statement from the chairman we feel the steps outlined previously will go a long way to alleviate a wide range of concerns."