The RIBA is facing a financial crisis that could lead to a raft of redundancies in the institute's staff and a potential cut in its service provision for members.
Accountants have warned the institute's ruling council that it needs to find an extra £5.7 million in the next 12 years if it is to avoid financial meltdown.
The problem centres on a final salary pension scheme the institute ran for staff until 1996, when former director general Alex Reid realised it was a timebomb and ordered it to be dropped.
However, problems with maintaining this pension fund at a healthy level emerged this year because of recent falls on the stock market.
A source on the RIBA council claimed that chief executive Richard Hastilow has briefed staff and councillors, warning them that redundancies are on the cards.
It is understood that the institute's leadership has been left with no choice because of its policy of freezing subscriptions over the next five years.
'Hastilow has warned that there will be job cuts if we are to keep the finances in order and not increase subs, ' the source told the AJ. 'And the council has dug its heels in and said that there should be no reduction in services for members.
'But how you reconcile a cut in RIBA employees and no reduction in the services provided is beyond me, ' the source added.
However, in an official statement, Hastilow denied that any final decisions had been taken.
'In the next business plan period - 2004-2006 - we have to meet these significant extra costs, either by increasing revenue or cutting expenditure.' The statement added: 'Proposals are currently being developed with boards, committees and staff, before bringing the draft business plan to the RIBA Council in October.'
RIBA president George Ferguson also played down the problems.
'All that we can say is that this situation requires us to look extremely hard at all our costs and incomes.
'But the one thing that is absolutely certain is that I will not sanction any increases in the subscription rate, ' he added.