core data with sqlcipher not saving BLOB data on external storage iOS

I am using SQLCipher to encrypt core data. It is working fine.
But the problem is the BLOB properties marked as "Allow External Storage" in core data are also saving inside sql file, even though BLOB is grater than 1MB.

When I was not using SQLCipher, it was saving these properties outside the sql file.

Any idea why it is happening?
OR if it is implemented so in SQLCipher, then is there any work around to save BLOB on external storage with encryption(other than iOS hardware inbuilt encryption)?