That claim is simply untrue. The partition plan defined the territory of the Jewish state *here*, and the territory of the Arab state *there*, and it is simply indisputable that when the 1949 Armistice was signed that the state of Israel was in control of fully twice as much territory as had been defined in the partition plan. That's an occupation, and it remained an occupation until 1993 when the PLO agreed to recognize the state of Israel as it existed at that point in time.
4 UN peacekeepers injured in Sinai and taken to hospital in south Israel (Haaretz)
from the article: Four years on, Netanyahu returns to Bar Ilan more hawkish than ever