The Queen met Barack Obama and his wife Michelle at Windsor Castle in April 2016 Credit: John Stillwell/PAHer Majesty with George W Bush in June 2008 Credit: Dominic Lipinski/PAWith Bill Clinton in December 2000 Credit: John Stillwell/PAThe Queen welcomed George Bush Snr in 1989 Credit: Martin Keene/PARiding with Ronald Reagan in 1982 Credit: Ron Bell/PAJimmy Carter was one of six world leaders who was a guest at a State Dinner in 1977 Credit: PAThe Queen with Gerald Ford during a visit to Washington in 1976 Credit: PARichard Nixon came over in October 1970 Credit: PAThe Queen and Duke of Edinburgh welcomed John F Kennedy and his wife Jacqueline in June 1961 Credit: PAWith Dwight D Eisenhower in summer 1959 Credit: PAHarry Truman with Princess Elizabeth in Washington in November 1951 Credit: PA