Marking a key as "don't export"?

[Dan McGee]

Is there any way to mark a key as local-only, similar to an
lsign-created local signature?

I'm asking because I plan on generating a master key to be used by a
piece of software where ultimate trust can be rooted, and there is
really no need to have even the public half of this key ever leave the
machine. The only operation it will ever be used in is lsigning
various other public keys.

-Dan