It's stop go...very expensive, very thwarting and not good news

Sir Richard Rogers

His comments followed a decision by Assembly First Secretary Rhodri Morgan to review all the options for the siting and costs of the new building.

Sir Richard expressed his wish that the building debate did not become a "political football".

The architect is due to meet with Assembly First Secretary Rhodri Morgan - who called in the building scheme for review in March - later this week in London.

It is understood they agreed to a meeting after speaking each other at the Hay literary festival this weekend.

Future vision: The proposed building

"It is very important to examine the situation," said Sir Richard, speaking at the festival.

"I am very optimistic that it will come out the right way. I hope it will not become a political football.

"I hope that there will be the spirit of community and innovation that was behind the original concept and I still very much hope that it will inspire what is very much a new country.

"It seems to me a great pity that we should be shoe-horning our spirits as well as our functional needs into an old and probably not suitable construction.

'Better future'

"It does show, I suppose, a serious lack of confidence in the future and that is sad.

"I would think political people would also feel, that what we are aspiring to is a better future."

He added: "It's stop go...very expensive, very thwarting and not good news."

Conservative AM Glyn Davies said Sir Richard had a "legitimate complaint" against the National Assembly over the threat to his design work.

But Mr Davies said the Conservative Assembly Group was adamant that the new building project should not go ahead.