WASHINGTON — John R. Bolton, President Trump’s national security adviser, defended on Tuesday the fact that neither Mr. Trump nor top national security officials had listened to audio of the killing of the Saudi journalist Jamal Khashoggi, saying that they did not speak Arabic and would not be able to understand what was on the tape.

During a nearly hourlong briefing focused on foreign policy, Mr. Bolton took the lectern at the White House and declined to answer repeated questions about why he had not listened to the recording provided by Turkish officials of the killing inside the Saudi Consulate in Istanbul.

“Why do you think I should?” Mr. Bolton asked reporters, suggesting he could read a transcript instead. “People who speak Arabic have listened to the tape, and they’ve given us the substance of what’s in it.”

Mr. Bolton’s comments came as Secretary of State Mike Pompeo and Defense Secretary Jim Mattis were preparing to brief the Senate on Wednesday about the circumstances surrounding Mr. Khashoggi’s death, which has prompted outrage among members of Congress.