I've seen evidence directly relating to or within the halo of the millennium development scheme.
You can read more about this UN goal here.
https://www.un.org/millenniumgoals/
see also
http://www.mdgfund.org/node/922
Which ironically you see it evolves into the un 2030 agenda that many conspiracy theorist have talked about. I think it is best to stay clear of these conspiraries unless there is proof, but it is interesting to see how the more you unravel things the more they come back to these people and their agendas.
https://undocs.org/A/RES/70/1
The millenium development might possibly be what was known as agenda 21.
I've read the basic arguments behind the conspiracy theory of reducing America down to 66 million people, but i don't see proof.