According to the ITV programme Wales This Week, the much-criticised £500 million Holyrood scheme was proportionally cheaper to build than Roger's waterfront effort in Cardiff Bay, which officially opened last week.
In the show, which is due to be screened tonight, it is claimed the Welsh Assembly cost £13,400 per square metre to build - compared to £13,060 for the over-budget parliament building in Edinburgh.
The programme goes on to attack senior government officials for covering up the true cost of the project which, officially, now stands at £67 million.
Paddy French, the programme's producer, feels the true expenditure on the scheme could be even higher.
He said: 'We believe [the ministers] are playing fast and loose on this and not telling us the whole story.'
The Wales This Weekclaims are the latest in a long line of allegations about the building and its budget.
Back in 2001 (AJ 25/10/2001) Rogers accused finance minister Edwina Hart of lying to the assembly about the scheme's spiralling costs when she declared the project was still on budget.
The Richard Rogers Partnership was unavailable for comment.