Prevent duplicating files in NuGet content and contentFiles folders

My NuGet package needs to deliver some rather large files to build output directory.

In an old NuGet model, such files have to be stored in content folder of the .nupkg. While in a new model introduced in NuGet 3.3, such files have to be stored in contentFiles folder.

To maintain a compatibility with older versions of NuGet and mainly with Package.config package management format, I need to duplicate the files into both folders. That unfortunately almost doubles a size of the package.

Is there a way to prevent that? Can I somehow link contentFiles to content folder?