The Rhodesians modelled their independence document on that of the American Thirteen Colonies in 1776, which remains the only other such proclamation in the history of the British Empire. According to UDI—which went unrecognised by Britain, the Commonwealth and the United Nations, all of which declared it illegal and imposed economic sanctions—the Rhodesian government still professed loyalty to Elizabeth II, whom it called the "Queen of Rhodesia". The British-appointed Governor, Sir Humphrey Gibbs, remained at his post in Government House, Salisbury, but was now ignored by the local government, which appointed its own "Officer Administrating the Government" to fill his ceremonial role. Smith represented Rhodesia in two abortive rounds of talks with Wilson, first aboard HMS "Tiger" in 1966, then on HMS "Fearless" two years later. Under Rhodesia's 1965 constitution, the Prime Minister remained at the head of Her Majesty's Rhodesian Government until 2 March 1970, when a republican constitution was adopted in line with the results of a referendum held the previous June. In the Republic of Rhodesia, the Prime Minister formally reported to the President.