How is the control of airspace over disputed territories determined? Reading this question about the division of airspace over the Persian Gulf reminded me of another potential issue regarding Persian Gulf airspace: the numerous territorial disputes in the area, such as the dispute between Iran and the United Arab Emirates over several islands (Abu Musa, the Greater and Lesser Tunbs, Sir Abu Nu'ayr, and Zirku) scattered over a large area of the lower end of the Gulf, and the unresolved issue of how far northwest the United Arab Emirates extend.

How is the ownership and control of the airspace over these and other disputed areas around the world (of which there are rather a lot) determined?
International air traffic control is divided into Flight Information Regions (FIR) by ICAO through international agreement. Normally this works fairly well. Even countries that are antagonistic to each other wish to maintain safe air traffic. 

Currently there is one situation that causes some real consternation, though. That's the dispute between Greece and Turkey over northern Cyprus. ICAO officially assigns the region to Greek ATC, but the northern part of Cyprus, which aligns with Turkey feels that the airspace is theirs and operates a separate ATC that  is not in cooperation with the official ATC, causing confusion for pilots.

They often create long and ridiculous notams to state their point.