Mike Waltz, Trump's pick for U.N. ambassador, to testify at Senate confirmation hearing

Washington — President Trump's pick to be U.S. ambassador to the United Nations, Mike Waltz, is set to testify Tuesday at his Senate confirmation hearing, the first time he'll publicly face questions from lawmakers about his role in a Signal chat in which top administration officials inadvertently disclosed sensitive details about a military strike in Yemen. 

The Senate Foreign Relations Committee hearing is scheduled to begin at 10 a.m., and Democrats have said they expect it will be "brutal" for Waltz. 

The role — the last of Mr. Trump's Cabinet to be confirmed — has been vacant for six months, leaving the U.S. without a top representative on a major world stage as several international crises play out.