A key US senator on Saturday said the Saudi crown prince was responsible for Jamal Khashoggi's murder and must be "dealt with", as he threatened new sanctions. Republican Lindsey Graham, an influential ally of President Donald Trump, has previously said that Crown Prince Mohammed bin Salman was complicit in the grisly killing of Washington Post contributor Khashoggi in October. "I have concluded that the relationship between Saudi Arabia and the United States cannot move forward until MBS has been dealt with," Graham said, using the initials for the crown prince. Graham also threatened new sanctions against those suspected of involvement...