Hi
You can use the User status profile and define two different statuses (example, one status is for Review and other one is for approval) by two authorities at different levels before releasing the project. Also you need to define two single roles and assign these authorization objects to enable one role for review and one for approval.
Discuss with your basis team for more information on setting up roles and building authorization objects.
Please check the forum for setting up user status profile because lots of discussions have been taken place in the past on this kind of issues which would give you more insight.
Thanks,
Sudhakar