RMGCGE5WBritain's Prime Minister David Cameron leaves the Home Office in Westminster, London.
RMDMYAB9Britain's Prime Minister David Cameron returns to Downing Street
RMDJ5FB7Britain's Prime Minister David Cameron (top), his wife Samantha (C) and Deputy Prime Minister Nick Clegg (bottom) attend a thanksgiving service to mark the Queen's Diamond Jubilee at St Paul's Cathedral in central London June 5, 2012. Four days of nationw
RMEFYN91(150212) -- BRUSSELS, Feb. 12, 2015 (Xinhua) -- Britain's Prime Minister David Cameron arrives at EU headquarters for an EU summit in Brussles, Belgium, Feb. 12, 2015. (Xinhua/Ye Pingfan)
RMFB0X10Munich, Germany. 07th Jan, 2016. Britain's Prime Minister David Cameron visits production lines at the BMW manufacturing plant in Munich, Germany, 07 January 2016. Photo: MARC MUELLER/dpa/Alamy Live News
RM2E6HTCFA guard of honour awaits as Britain's Prime Minister David Cameron arrives in Amman in Jordan September 14, 2015. REUTERS/Stefan Rousseau/pool
RMD56FE6US President Barack Obama and Britain's Prime Minister David Cameron attend the session on Russia during the NATO summit conference at Lisbon, Portugal, 20 November 2010. Photo: RAINER JENSEN
RMTYBH09Britain's Prime Minister David Cameron (R) meets with American Vice President Joe Biden at No.10 Downing St, London on February 5, 2013. UPI/Hugo Philpott
RM2E1680WBritain's Prime Minister David Cameron and wife Samantha arriving at Westminster Abbey for the wedding of Prince William to Kate Middleton, in London, UK on April 29, 2011. Photo by Frederic Nebinger/ABACAPRESS.COM
RMRJHN0FAung San Suu Kyi meets with Britain's Prime Minister David Cameron on October 23, 2013, at 10 Downing Street in London.
RM2EWFFK2Britain's Prime Minister David Cameron gives a speech before leaving 10 Downing Street in London, Britain on July 13, 2016. (Xinhua/Han Yan) (Photo by Xinhua/Sipa USA)
RMG47KMEBritain's Prime Minister David Cameron talks to hospital staff at Frimley Park Hospital.
RMDMYAE7Britain's Prime Minister David Cameron returns to Downing Street