Israel's occupation of Palestine, which has continued since 1967 and is the longest military occupation in modern history, has become illegal under international law. This illegality encompasses the West Bank, including Israeli-annexed East Jerusalem, as well as the blockaded Gaza Strip, which remains to be considered occupied under international law despite the 2005 Israeli disengagement. Israel's policies and practices in the occupied West Bank, including the construction and expansion of Israeli settlements, have amounted to de facto annexation that is illegal under international law.
It is a subject that has received much less attention than violations of international humanitarian law (IHL) and international human rights law (IHRL) that have occurred during the occupation. Multiple United Nations General Assembly resolutions have described the continuing occupation as illegal. The general thrust of international law scholarship addressing this question has concluded that, regardless of whether it was initially legal, the occupation has become illegal over time. Reasons cited for its illegality include use of force for impermissible purposes such as annexation, violation of the Palestinian right to self-determination, that the occupation itself is an illegal regime "of alien subjugation, domination and exploitation", or some combination of these factors. Eyal Benvenisti suggested that refusal by an occupier to engage in good faith with efforts to reach a peaceful solution should not only be considered illegal but as outright annexation. International law scholar Ralph Wilde states that "The common way of understanding the extended duration of the occupation... is a prolonged violation of international law". Israel denies occupying Palestine and maintains its presence is legal.