UN Security Council resolution 365 makes this perfectly clear: "The Security Council ... 5. Determines that all measures taken by Israel to change the physical character, demographic composition, institutional structure or status of the Palestinian and other Arab territories occupied since 1967, including Jerusalem, or any part thereof have no legal validity and that Israel's policy and practices of settling parts of its population and new immigrants in those territories constitute a flagrant violation of the Geneva Conventions relative to the Protection of Civilian Persons in Time of War and also constitute a serious obstruction to achieving a comprehensive, just and lasting peace in the Middle East." While the Geneva Conventions, by their own terms, have limited applicability, the principles and prohibitions therein have been adopted by the UN as universally applicable. The applicability thereof to the WB, including Jerusalem, is specifically affirmed in this resolution.
from the article: Lieberman: U.S. demand to end East Jerusalem building is 'unreasonable'