Sports Minister Edwin Poots has revealed that his department has spent £3,397,835 so far on the proposals to build a multi-sports stadium on the site of the former high security jail.

In answer to a written question from Lagan Valley MLA Paul Butler, the DUP minister said the majority of the money — £ 2,953,370 — has been incurred on stadium design.

Another £444,465 has been spent by the Department of Culture, Arts and Leisure on business planning, management and other consultancy costs linked to the stadium project.

But Sunday Life can reveal that senior civil servants have refused to back plans for a 38,500 seater stadium.

It is understood that an assessment from the Department of Culture Arts and Leisure was submitted without the endorsement of the Permanent Secretary.

The absence of support from key civil servants in the departments principally involved in the project to build a national stadium on the former prison site is likely to put the final nail in its coffin.

Reports sent to Finance Minister Peter Robinson are understood to outline the long term financial risks to the taxpayer of building a 'national stadium' at the Maze, which will only utilise its planned 38,500 capacity once a year.

And critics have pointed out that building it would cost more than double the outlay on a 30,000 seater venue.

One senior civil servant said: "To spend at least double the revenue just to insert an extra 8,500 seats in the plan doesn't make financial sense. Even a 30,000 seater stadium raises the essential question of what it is going to be used for and how often it is going to be used.

"Ulster rugby has indicated plans to refurbish Ravenhill. Is it going to do that and then leave it unused to play at the Maze? The 38,500 seater stadium isn't economically viable and there are major financial questions about building a 30,000 stadium there."

Other 'added value' factors have also been dissected by civil servants and found to be less than compelling, informed sources say.

"Overall the Maze Stadium proposal doesn't stack up economically and without it the original business plan for the redevelopment of the site isn't viable either," the civil servant said.

On Friday, Peter Robinson said that the Maze site should be developed for another purpose and fully utilised if the decision was made not to proceed with the stadium proposal. He will make a recommendation to the Executive on the stadium plan before he takes up the reins of First Minister later this month.

The Office of First Minister and Deputy First Minister declined to comment.