Merge two LVM volume group

Hi! There is a possibility to merge 2 distinct volume group in proxmox?
I've 2 volume group

vg0 => /var/lib/vz => 100GB without free PE
vg1 => /backup => 200GB with 70GB free PE

Of cource now I cannot do a snapshot in vg0 because I haven't enough free PE..Can I move the avaiaible free PE in VG1 into VG0 and use that for snapshot?

Thanks.