What can ICAO do to prevent States from conducting missile tests or other activities which may endanger civilian air traffic?
Sovereign States, and not ICAO, are suitably responsible for advising other States and aircraft operators of any risks to civil aviation safety or security which may arise from activities in their sovereign territories or airspace. States are similarly responsible for restricting aircraft operations over their territories, whether completely or to various pre-determined flight levels, depending on the severity of the risk.
In situations when a State may be planning a missile test or other type of aerial operation which may pose dangers to local civilian flights, it is its responsibility to notify adjacent States and locally-operating airlines concerning the precise nature of the risk, and the specific flight areas which may be impacted.
In certain circumstances, for instance where a State wishing to share risk information may not have effective diplomatic relations with its adjacent States, the State seeking to promulgate the risk details may request that ICAO undertakes the required information sharing on its behalf.