Is there an --des-key-file equivalent for AES?

When you use the DES_ENCRYPT/DES_DECRYPT function in mySQL you can point to your keyfile from my.cnf using the --des-key-file variable.

I thought this should also exist for

AES_ENCRYPT/AES_DECRYPT 

So I searched for hours but couldn't find it: is there an equivalent for AES for this?