The Balfour Declaration of 1917 (dated November 2, 1917) was a classified formal statement of policy by the British government stating that the British government "view with favour the establishment in Palestine of a national home for the Jewish people" with the understanding that "nothing shall be done which may prejudice the civil and religious rights of existing non-Jewish communities in Palestine, or the rights and political status enjoyed by Jews in any other country."

The declaration was made in a letter from Foreign Secretary Arthur James Balfour to Lord Rothschild (Walter Rothschild, 2nd Baron Rothschild), a leader of the British Jewish community, for transmission to the Zionist Federation, a private Zionist organization. The letter reflected the position of the British Cabinet, as agreed upon in a meeting on October 31, 1917. It further stated that the declaration is a sign of "sympathy with Jewish Zionist aspirations."

The statement was issued through the efforts of Chaim Weizmann and Nahum Sokolow, the principal Zionist leaders based in London but, as they had asked for the reconstitution of Palestine as “the” Jewish national home, the Declaration fell short of Zionist expectations.^[1]

The "Balfour Declaration" was later incorporated into the Sèvres peace treaty with Turkey and the Mandate for Palestine. The original document is kept at the British Library.