Swift and Objc in a Static lib

I have a lib that I also distribute with cocoapod, and the project has both Swift and Objc code.

Im using modules to expose objc private classes to Swift, but some of this private classes also have a reference to the public objc classes.

Then the compiler complains about "Duplicate interface definition"

This does not happen if the project is created as a framework, but I have not control how the project will be used as.

Any suggestion?