The agreement signed by Israeli upon admission to the U.N. Limited it's territory and rights to annex territories and in that sense there is no dispute that the 'disputed' territories do not belong to Israel. The problem arises as to whom the territories belong. Given the liberal democratic underpinnings of modern international law, one would have to conclude that the inhabitants have the right to assert self determinative sovereignty which as you point out, is a political question.
U.S. sanctions Russia's state-owned arms exporter Rosoboronexport (Reuters)
from the article: Incitement Day in Jerusalem