KYIV, Jan 19 (Reuters) - U.S. Secretary of State Antony Blinken on Wednesday said the United States will continue relentless diplomatic efforts to prevent Russian aggression in Ukraine, following his meeting in Kyiv with Ukrainian President Volodymyr Zelenskiy. Should Russia carry through with aggressive intent toward Ukraine, the United States would provide additional material to the ex-Soviet country beyond that which is already in the pipeline, Blinken told reporters in Kyiv during a press conference with Ukrainian Foreign Minister Dmytro Kuleba.