build-deps non non-US does not implies archiving in non-US?

[Francesco Paolo Lovergine <frankie@debian.org>]

As I can read from policy 2.1.5:

"A package depends on another package which is distributed via the non-us
server has to be stored on the non-us server as well."

How this rule should be interpreted for Build-deps and Suggests?
Can a non non-US pkg Build-dep on or Suggest a non-US pkg?

My guess is that the non-US limitation refers to _distribution_ of
binaries. So a GPL package which Build-deps on a non-US one, but which
does not Depends on it, could anyway stay in main archive.
The same if it Suggests only, not Depends on it.

Is this correct? 

If not, maybe a clarification in Policy is a good thing.

-- 
Francesco P. Lovergine