A computer generated image of the new debating chamber

Details of how �10.8m will be spent on computer equipment, furniture and art have been released.

The Tories said this amount added millions to the running total for the cost of the project.

But the assembly government said it had always been open about costs and the building was value for money.

When work for the new chamber restarted in July last year, the total cost was said to be between �50m and �55m.

That figure included �40m for the building itself, up to �7m in VAT and �7.5m already spent on groundwork before work on the project was halted in 2001.

It's very easy to throw money away when it's somebody else's. We must remember this is tax-payers' money Tory AM Jonathan Morgan

In March this year, an assembly publication said the cost of building the chamber had been fixed with Taylor Woodrow Construction at �40.997m.

It made clear that the figure excluded VAT on construction costs, professional fees for project management, furniture, information and communication technology equipment, broadcasting equipment, art and other professional fees.

The assembly has now outlined that �6.7m will go on IT and media equipment, �1.6m on furniture, �300,000 on art and �2.2m on professional fees.

While the cost of the building itself has not gone up, the Conservatives have said that the running total of money being spent on it is still rising.

Jonathan Morgan, Tory AM for South Wales Central, said: "It's very easy to throw money away when it's somebody else's money and we must remember this is tax-payers' money. This is not government money.

The new chamber will sit on the Cardiff Bay waterfront

"The fact of the matter is this is way over budget, it's way over cost, it's way beyond what was originally anticipated. It's a palace for politicians. There's no great public support out there."

The assembly government defended the costs, saying it had been very open about money going into the project. It also said the building's 100-year lifespan represented value for money.

Lorraine Barrett, Labour AM for Cardiff South and Penarth, said: "The problem is public buildings always cost more than you first anticipate and there are costs.

"We do take the public purse seriously and I think Sue Essex is a prudent finance minister.