The guidance, issued for consultation in March, is strongly in favour of preserving historic buildings in the 70% of the London borough covered by conservation areas, the historic skyline of Westminster, and important strategic and local views.
It rules against high buildings on the grounds that "their impact may not only be disruptive to the local street scene, but also detrimental to the city as a whole and to views of the London skyline from strategic viewpoints and elsewhere".
It adds that: "Existing high buildings or groups of high buildings should not set a pattern for further high buildings on adjacent sites."
CABE chief executive Jon Rouse said: "Westminster is in danger of turning the borough into a museum piece by insisting on the slavish imitation of the past."
Rouse said CABE would be making detailed comment to Westminster in the hope that the two would be able to work together to produce guidance that will promote high-quality architecture in future.