A raft of those entering the contest, to design a new observatory in the hills surrounding Kielder village, Northumberland, have secretly voiced fears to the AJ about the project's tiny budget.
Although hailed as an 'aspirational- key project' by the competition's backers, the Kielder Partnership, many architects believe the £125,000 price tag makes the brief almost impossible.
One architect, who wanted to remain anonymous, said: 'All of us know that Kielder wants 'architecture' so this means we think it is unachievable.
'I guess you can build something for £125,000 but it will be a basic Christmas tree without the lights, fairy and tinsel!'
Other entrants have recommended the cash should be upped to allow a proper appraisal of the possible options.
'We thought this competition could be really fantastic, if only we had the budget,' said another architect. '[the Kielder Partnership] were really pushing for something ambitious so it is a frustrating given their aspirations. We had to make compromises as part of our project, especially with our construction, where we went very cheap.'
He added: 'A budget of £140,000 would have made things more achievable and we showed them what we could have done - even with a budget of just an extra £15,000.
However, south London-based architect Ian McChesney, who decided against entering, was not surprised by the amount of the available funding and thought it likely the winning scheme could cost more than anticipated by the contest's organisers.
He said: 'It's very common for these types of competition to have optimistic budgets. The competition situation may encourage the most ambitious design, but it's rare for costs to be properly scrutinised by juries on this size of competition. Often the winning design is over budget.'
The contest's shortlist is expected to be announced by the RIBA Competitions office within the next few weeks.