Who must approve a globally distributed satellite to ground laser communication system?
(I've taken a wild stab at an answer, despite my not being a lawyer or legal expert of any kind, since nobody has written an answer in nearly four years.  If you don't like my answer, please feel free to write a better one.  I apologize in advance if I've abuse any legal terms.  It's quite possible that I have come to an erroneous conclusion.)
Your question seems to presume that there is some multinational body, or multinational rules, governing laser beams in the atmosphere.  However, there is no multinational agreement to regulate laser beams in the atmosphere.
Countries are sovereign, with no higher legal authority, and are not required to make any rules, laws, or enforcement bodies without voluntarily agreeing to do so.  Often countries realize that uniform standards or regulations are in their best interests, and make treaties or agreements with other countries to create laws and rules and enforce them.  Sometimes countries voluntarily abide by existing treaties or agreements without actually signing onto the agreement.  In the absence of such formal treaties or agreements between countries, individual countries are free to write, or to not write, whatever rules and laws they like.
One of the functions of the United Nations is to create a list of international treaties and agreements.  The list, known as the United Nations Treaty Series Cumulative Index, can be found here.  The most recent list as of this writing, current to 20 March 2013, sorted alphabetically, is here.  A quick search of the index for the term &quot;laser&quot; reveals only an &quot;Exchange of notes constituting an agreement between the United States and Japan concerning a program for the cooperative research of Eyesafe Laser Radar.&quot;
In other words, there is no multinational agreement to create rules or laws regarding laser beams in the atmosphere, other than those that pertain to aviation safety.  Existing aviation safety legislation seems to agree that pointing powerful lasers at aircraft is something that should be regulated.  However, it seems likely to me that aviation safety treaties are silent regarding laser beams through the atmosphere that are not pointed at aircraft.
To sum up, it has been left to individual countries to write whatever laws they like regarding laser beams in the atmosphere not aimed at aircraft.  Currently it seems likely that few countries have written any such laws.  So companies can currently feel free to plan communications networks using laser beams between ground stations and satellites, since there are few or no laws to stop them, as long as they take care to not accidentally aim laser beams at aircraft.