Hat tip to MenorahBlog:
The last legally binding document to be adopted regarding the areas of Israel in question remains the 1920 San Remo resolution, which deeds full sovereignty to the Jewish people.
San Remo Resolution. This resolution, consisting of the Balfour Declaration and Article 22 of the Covenant of the League of Nations, is the basic document upon which the Mandate for Palestine was constructed. The San Remo Resolution concerning Palestine and the Jewish National Home was adopted at the San Remo Peace Conference on April 25, 1920 by the four Principal Allied Powers of World War I who were represented by the Prime Ministers of Britain (David Lloyd George), France (Alexandre Millerand) and Italy (Francesco Nitti) and by the Ambassador of Japan (K. Matsui).
The Resolution was a binding agreement between these Powers to reconstitute the ancient Jewish State within its historic borders “from Dan to Beersheba”, an agreement that was incorporated into the Treaty of Sevres and the Mandate for Palestine. Jerusalem Newswire