British Jews celebrated the 90th anniversary of the Balfour Declaration on Wednesday night at a ceremony in the very halls where discussions that led to the declaration calling for a revived Jewish national home were held. More than 300 people attended the UK Zionist Federation event at the Foreign Office's Locarno Suite in Whitehall, central London. The guest speaker was Sir Martin Gilbert, the official biographer of Winston Churchill. Lord Jacob Rothschild, great-nephew of Lord Walter Rothschild, to whom foreign secretary Arthur James Balfour addressed the Declaration, introduced Gilbert, who gave a keynote speech on Churchill's involvement in the creation of the State of Israel. Gilbert also discussed World Zionist Organization president Chaim Weizmann's part in securing a commitment form the British government for a homeland for the Jewish people. Persuading the Russians to stay in World War I was vital for Britain, Gilbert said, and Russian Jews were thought to be key to securing this. Gilbert said Wiezmann persuaded the British government that a declaration in favor of a Jewish national home in Palestine, providing Turkey could be defeated, would help achieve this. According to Gilbert, Churchill thought that by creating Transjordan in 1921 on 77 percent of Mandatory Palestine, he had saved the project for a Jewish national home because King Abdullah understood that the rest of the land was for the Jews. Weizmann, Gilbert said, sent Churchill a letter 34 years later thanking him for this decision. "I want to thank you for what you did in 1921, that you laid the foundation to the Jewish state by separating Abdullah's kingdom from the rest of Palestine. Without this there would not have been an Israel today," Gilbert said Weizmann wrote. The event closed with the singing of Hatikva and every guest received a signed copy Gilbert's book Churchill and the Jews and a first day cover to commemorate the anniversary.