The Regency Society's comments follow both CABE and English Heritage publicly backing the scheme. The society said it has no option left but to campaign for the £290 million scheme to be called in.
A report by the Regency Society said: '[The society] is convinced that the choice of this team, led by Frank Gehry, should not lead to suspension of normal critical appraisal of any proposals put forward.
'Our views have been strengthened by the apparent acceptance by council leaders of all of Gehry's schemes for this site - even those that Gehry later disowned as being unsuitable.
'We are reinforced in our concern by CABE's letter of 23 October 2006, which stated: 'Given the long-term involvement of the architect, we are confident that the issues we raise can be addressed. We do not wish to see this project again.'
'This appears to suggest that Gehry's reputation enables his project to avoid the checks and scrutiny that lesser architects undergo,' the report concludes.
The report is the final document the Regency Society plans to issue on the scheme. Society secretary John Small said: 'We have said all we can say on the matter and we will now be campaigning for the development to be called in.
'We believe it is an overdevelopment of the site, as the original local plan brief called for 200-400 units; this has more than 700. It is an oppressive development, which will even be oppressive on the public spaces it plans to provide.'