Masterplanners Allies and Morrison and EDAW are to team up on the development.
Allies and Morrison is working on the Cricklewood site for Pillar and EDAW is drawing up plans for Brent Cross for Hammerson, which owns the Brent Cross shopping centre.
The Cricklewood development is jointly funded by Hammerson and Pillar, and the plans for Brent Cross will be backed by Hammerson and Standard Life Investments.
A spokesperson for Cricklewood Redevelopment said the firms hoped to finalise plans for the sites this year. He said: "There are no firm dates as yet but we hope to have a development framework set out some time this year."