Queen Elizabeth II (L) stands with US President Barack Obama and First Lady of the United States, Michelle Obama in the Oak Room at Windsor Castle ahead of a private lunch hosted by the Queen on April 22, 2016 in Windsor, England. (Photo by John Stillwell - WPA Pool/Getty Images)
President Obama And The First Lady Lunch With The Queen and Prince Philip
US President Barack Obama, First Lady Michelle Obama and Queen Elizabeth II arrive at the Sovereign's Entrance in the Quadrangle of Windsor Castle after landing by helicopter at Windsor Castle for a private lunch on April 22, 2016. (Photo by Geoff Pugh - WPA Pool/Getty Images)
President Obama And The First Lady On Brief Visit To London
A motorcade drives into Windsor Castle during the arrival of US President Barack Obama and First Lady Michelle Obama at Windsor Castle ahead of a lunch with Queen Elizabeth II on April 22, 2016 in London, England. (Photo by Ben Pruchnie/Getty Images)
US President Barack Obama (2R) and his wife US First Lady Michelle Obama (R) are greeted by Britain's Queen Elizabeth II (2L) and Prince Philip, Duke of Edinburgh, (L) after landing by helicopter at Windsor Castle for a private lunch in Windsor, southern England, on April, 22, 2016. (ALASTAIR GRANT/AFP/Getty Images)
Britain's Queen Elizabeth II (2nd L) and her husband Prince Philip, Duke of Edinburgh (L) greet US President Barack Obama (R) after he and his wife Michelle arrived by helicopter outside Windsor Castle, west of London, on April 22, 2016.
( JIM WATSON/AFP/Getty Images)
President Obama And The First Lady On Brief Visit To London
(Photo by John Stillwell - WPA Pool/Getty Images
President Obama And The First Lady On Brief Visit To London
US President Barack Obama (2R) and his wife US First Lady Michelle Obama (R) are greeted by Britain's Queen Elizabeth II (2L) and Prince Philip, Duke of Edinburgh, (L) after landing by helicopter at Windsor Castle for a private lunch in Windsor, southern England, on April, 22, 2016. (ALASTAIR GRANT/AFP/Getty Images)
President Obama And The First Lady On Brief Visit To London
US President Barack Obama (L) and his wife Michelle prepare to leave Winfield House in central London on April 22, 2016, on their way to meet with Britain's Queen Elizabeth II and her husband Prince Philip, Duke of Edinburgh.
( JIM WATSON/AFP/Getty Images)
President Obama And The First Lady On Brief Visit To London
US President Barack Obama (2R) and his wife US First Lady Michelle Obama (R) are greeted by Britain's Queen Elizabeth II (2L) and Prince Philip, Duke of Edinburgh, (L) after landing by helicopter at Windsor Castle for a private lunch in Windsor, southern England, on April, 22, 2016. (ALASTAIR GRANT/AFP/Getty Images)
The Obamas Visit England
British Prime Minister David Cameron (R) poses for pictures with US President Barack Obama before a meeting in 10 Downing Street in central London on April 22, 2016.
( JIM WATSON/AFP/Getty Images)
The Obamas Visit England
British Prime Minister David Cameron (R) speaks with US President Barack Obama before a meeting in 10 Downing Street in central London, on April 22, 2016.
(JIM WATSON/AFP/Getty Images)
