Using relative paths in .mbedignore file

Is it possible to use relative paths in .mbedignore file? I am looking to ignore files which are in backward directories from current directory:

|-> projects
|-> project1
|-> .mbedignore

|-> library1

From .mbedignore file in the project directory above, I want to ignore few files from the Libraries/library1 directory. Is this possible to do and if yes, how can I add relatives path in mbedignore file?
If relative paths doesn’t work, any alternative for this?