MANAMA, BAHRAIN - DECEMBER 07: British Prime Minister, Theresa May, attends a plenary session on the second day of the Gulf Cooperation Council summit, on December 7, 2016 in Manama, Bahrain. Prime Minister May is meeting Gulf leaders during the annual two-day Gulf Cooperation Council where she has discussed regional issues including the situations in Yemen and Syria and the perceived regional threat posed by Iran. (Photo by Carl Court/Getty Images)

MANAMA, BAHRAIN - DECEMBER 07:  British Prime Minister, Theresa May, attends a plenary session on the second day of the Gulf Cooperation Council summit, on December 7, 2016 in Manama, Bahrain. Prime Minister May is meeting Gulf leaders during the annual two-day Gulf Cooperation Council where she has discussed regional issues including the situations in Yemen and Syria and the perceived regional threat posed by Iran.  (Photo by Carl Court/Getty Images)

MANAMA, BAHRAIN - DECEMBER 07: British Prime Minister, Theresa May, attends a plenary session on the second day of the Gulf Cooperation Council summit, on December 7, 2016 in Manama, Bahrain. Prime Minister May is meeting Gulf leaders during the annual two-day Gulf Cooperation Council where she has discussed regional issues including the situations in Yemen and Syria and the perceived regional threat posed by Iran. (Photo by Carl Court/Getty Images)

MANAMA, BAHRAIN - DECEMBER 07: British Prime Minister, Theresa May, attends a plenary session on the second day of the Gulf Cooperation Council summit, on December 7, 2016 in Manama, Bahrain. Prime Minister May is meeting Gulf leaders during the annual two-day Gulf Cooperation Council where she has discussed regional issues including the situations in Yemen and Syria and the perceived regional threat posed by Iran.  (Photo by Carl Court/Getty Images)

MANAMA, BAHRAIN - DECEMBER 07: British Prime Minister Theresa May (L) meets Sheikh Tamim bin Hamad Al Thani, the Emir of Qatar, during a bilateral meeting at the Gulf Cooperation Council summit, on December 7, 2016 in Manama, Bahrain. Prime Minister May is meeting Gulf leaders during the annual two-day Gulf Cooperation Council where she has discussed regional issues including the situations in Yemen and Syria and the perceived regional threat posed by Iran. (Photo by Carl Court - Pool/Getty Images)

MANAMA, BAHRAIN - DECEMBER 07:  British Prime Minister Theresa May (L) meets Sheikh Tamim bin Hamad Al Thani, the Emir of Qatar, during a bilateral meeting at the Gulf Cooperation Council summit, on December 7, 2016 in Manama, Bahrain. Prime Minister May is meeting Gulf leaders during the annual two-day Gulf Cooperation Council where she has discussed regional issues including the situations in Yemen and Syria and the perceived regional threat posed by Iran.  (Photo by Carl Court - Pool/Getty Images)