Some retailers in and around High St have already moved. Zambesi, World and Kate Sylvester left High St for Britomart and bespoke tailor RJB has also moved to a Britomart building on Customs St.
International labels such as L'Occataine and Ted Baker are housed in the new Westpac building.
The shops are scheduled to open just before Christmas, Mr Cockram said, and cafes will also be built there.
For nearly two decades, Karen Walker has sold her lines from character premises at 15 O'Connell St.
Jiali Yang, the brand's PR and showroom manager, said the store opened in November 1994.
Walker said the shift made sense for a number of reasons.
"We're looking for a dramatic space for our flagship city store. O'Connell St was the second store we opened, almost 20 years ago now.
"It's been great throughout that time but it does have limitations in terms of the space - its frontage, footprint, stud, etc.
"It would also allow a much more complete presentation with the full offering of clothing lines, fine jewellery and eyewear as well as new products to be released later this year."
Denise L'Estrange-Corbet of World has praised the Britomart environment, from its hand-picked restaurateurs, bar owners and retailers to the bean bags on the lawn in Takutai Square.
"It's what Queen St should have been - instead it's absolutely appalling. There's no vision.
"Landlords don't care - they'll let to whoever wants to pay the rent," she said this year.
Mr Cockram said a new bistro-cafe area would also be developed in the midst of the fashion hub.
The area would be run by restaurateurs Scott Brown and Jackie Grant, of Hip Group, which has the Richmond Rd Cafe, Takapuna Beach Cafe, Cafe on Kohi and Rosehip Cafe in Parnell.
He said pavilion-like structures had been designed by Nat Cheshire of Cheshire Architects.
Britomart would have 33 fashion, beauty and specialty stores once The Pavilions was finished, he said.
A series of towers averaging nine levels are still planned, but in the longer term because there was not yet the market for them.
The Pavilions will be a single-level development.