Former national security adviser Mike Waltz will testified before the Senate on Tuesday on his nomination for U.S. ambassador to the United Nations.

Waltz, who left his previous post in May after controversy surrounding the Trump administration’s use of the Signal messing app, faced questioning before the Senate Foreign Relations Committee. The confirmation hearing is likely to focus on his mishandling of sensitive military operations during his time as the chief of the National Security Agency.

Secretary of State Marco Rubio was tapped to lead NSA after Waltz’s departure and following President Trump’s pulling of New York Rep. Elise Stefanik (R) as the nominee a dual role that had not been held since Henry Kissinger was in office during the Nixon and Ford administrations.

The hearing was scheduled to begin at 10 a.m. EDT.

Watch the video coverage above.