Yes, you will need Internet connectivity in order to access the menus of the application. When you start the application a login window will appear asking you to enter your credentials. Those credentials are verified on the servers, but if there is no Internet connection, an error will be shown instead.
Unfortunately, there isn't anything you can do to overcome this since this is the way the application is developed to run on released platforms. The same applies for mobile versions as well. If no Internet connectivity is found, the software won't be accessible.