U.S. Senator Lindsey Graham, a Republican from South Carolina who evolved from a vocal critic of Donald Trump into one of the president's closest allies, has died at the age of 71 after a "brief and sudden illness," according to his office.
President Trump said Graham had appeared well after returning from a trip to Ukraine and announced that U.S. flags would be lowered in his honor.
South Carolina Governor Henry McMaster is expected to appoint a temporary replacement before Republicans select a nominee for the November midterm election.
Graham's death removes a Republican vote in the closely divided Senate but is not expected to alter the broader balance of power because South Carolina remains a reliably Republican state.
Graham was widely known for his hawkish positions on U.S. foreign policy, including strong support for military aid to Ukraine, support for Israel, and calls for increased pressure on Iran.
His positions drew both support and criticism in the United States and abroad.
Days before his death, he met Ukrainian President Volodymyr Zelenskyy in Kyiv to discuss Ukraine's air defense needs and proposed sanctions on Russia.
Zelenskyy said he was "deeply saddened" by Graham's death and noted the senator had visited Ukraine 10 times since Russia's full-scale invasion in 2022.
Israeli Prime Minister Benjamin Netanyahu said he had lost "a beloved friend."
Graham also backed U.S. military interventions in Iraq, Syria, and Libya and advocated tougher measures against Iran, making him a polarizing figure throughout his Senate career.
Graham was elected to the House of Representatives in 1994 before joining the Senate in 2002.
As chairman of the Senate Judiciary Committee, he oversaw confirmation proceedings for more than 200 federal judges during Trump's first administration.
Although Graham sharply criticized Trump during the 2016 presidential campaign, the two later developed a close political relationship despite occasional public disagreements.
Representative Michael McCaul said Congress should pass Graham's proposed Russia sanctions legislation following his death.
Graham never married and lived in Seneca, South Carolina.