late April 1949, the Commonwealth leaders issued the London Declaration, which laid the foundation of the modern Commonwealth and recognised George as Head of the Commonwealth. In January 1950, he ceased to be King of India when it became a republic. He remained King of Pakistan until his death. Other countries left the Commonwealth, such as Burma in January 1948, Palestine (divided between Israel and the Arab states) in May 1948 and the Republic of Ireland in 1949. In 1947, George and his family toured southern Africa. The prime minister of the Union of South Africa, Jan Smuts, was facing an election and hoped to make political capital out of the visit. George was appalled, however, when instructed by the South African government to shake hands only with whites, and referred to his South African bodyguards as "the Gestapo". Despite the tour, Smuts lost the election the following year, and the new government instituted a strict policy of racial segregation. Illness and death The stress of the war had taken its toll on George's health, made worse by his heavy smoking, and subsequent development of lung cancer among other ailments, including arteriosclerosis and Buerger's disease. A planned tour of Australia and New Zealand was postponed after George suffered an arterial blockage in his right leg, which threatened the loss of the leg and was treated with a right lumbar sympathectomy in March 1949. His elder daughter and heir presumptive, Elizabeth, took on more royal duties as her father's health deteriorated. The delayed tour was re-organised, with Princess Elizabeth and her husband, Philip, Duke of Edinburgh, taking the place of the King and Queen. George was well enough to open the Festival of Britain in May 1951, but on 4 June it was announced that he would need immediate and complete rest for the next four weeks, despite the arrival of Haakon VII of Norway the following afternoon for an official visit. On 23 September 1951, he underwent a surgical operation where his entire left lung was removed by Clement Price Thomas after a malignant tumour was found. In October 1951, Elizabeth and Philip went on a month-long tour of Canada; the trip had been delayed for a week due to George's illness. At the State Opening of Parliament in November, the Lord Chancellor, Lord Simonds, read the King's speech from the throne. The King's Christmas broadcast of 1951 was recorded