How to mount .iso file from NFS share?

[MRH <misiek_spam@o2.pl>]

Good evening all :)

I hope it's not off-topic. I have a problem with mounting an .iso file 
from a mounted NFS share on my Debian sid. The NFS share is mounted in 
my home subdirectory (by fstab):
$ cat /etc/fstab
...
nfsserver:/user0 /home/user0/test nfs defaults,bg 0 0
...

$ ls ~/test
MyCD.iso

$ sudo mount /home/user0/test/MyCD.iso /home/user0/CD -t iso9660 -o lo,ro
/home/user0/test/MyCD.iso: Permission denied

Why? And how can I mount the .iso file? NB, when I copy the .iso file to 
my local folder I can mount it without any problems.

Kind regards,
--
Michal R. Hoffmann