In November 2017, Murphy accused the United States of complicity in the war crimes committed in Yemen by the Saudi-led military coalition and in Yemen's humanitarian crisis, saying: "Thousands and thousands inside Yemen today are dying. ... This horror is caused in part by our decision to facilitate a bombing campaign that is murdering children and to endorse a Saudi strategy inside Yemen that is deliberately using disease and starvation and the withdrawal of humanitarian support as a tactic." In October 2018, Murphy wrote that if the reports of Jamal Khashoggi's murder are true, "it should represent a fundamental break" in Saudi Arabia–United States relations. Murphy, along with Bernie Sanders and Mike Lee, advanced a vote to co-sponsor a resolution that would require the President to "withdraw troops in or "affecting" Yemen within 30 days unless they are fighting al Qaeda." In February 2019, Murphy was one of seven senators to reintroduce legislation requiring sanctions on Saudi officials involved in the killing of Jamal Khashoggi and seeking to address support for the Yemen civil war through prohibiting some weapons sales to Saudi Arabia and U.S. military refueling of Saudi coalition planes.