The government has allocated £15m to the project to open railway stations at Moseley, Kings Heath and Hazelwell.
Planning applications are set to be submitted for Kings Heath and Hazelwell, with an application for Moseley expected to follow later this year.
It is hoped that construction work would start in 2020, with a view to getting the three stations open in time for the 2022 Commonwealth Games.
The stations are located on a railway line that is currently used for freight and non-stop trains. Until recently, the project was expected to require the Camp Hill chord so that trains could access Birmingham Moor Street. However, work has identified opportunities to use the existing line into Birmingham New Street.
Source: WMCA