In less than a month Bath and North East Somerset Council has received nearly 100 written objections to the application from protesters including former architects, local residents and even a monk.
In a letter to the council Serota said: 'The extension provides such facilities in a form which acknowledges the pre-eminence of the original building and adopts the language of restrained Modernism to balance the calm elegance of the main structure.'
But objectors to the project feel the Parry proposals are 'alien' to the historic surroundings and detract from the existing Classical, Bath stone museum building.
It is also claimed the scheme contravenes the local plan and Planning Policy Guidance 15 on the historic environment.
Surprisingly, the Bath Preservation Trust has taken the unusual step of walking away from the debate by declaring it can neither support nor object to the plans.
Meanwhile a former member of the authority's planning committee described the situation - which has divided the city - as posing the 'most difficult decision' for the council in the last 20 years.
The scheme is expected to go before the planning committee on July 11.