In a heated Senate confirmation hearing for Pete Hegseth, Sen. Tammy Duckworth grilled the proposed defense secretary over the Association of Southeast Asian Nations, asking him if he could name one member and how many countries were in the bloc.

Pete Hegseth, President-elect Donald Trump’s pick for defense secretary, was questioned about ASEAN during a heated Senate confirmation and struggled with his response.

Hegseth responded at the heated Senate confirmation hearing that he couldn’t tell Duckworth the exact number of ASEAN nations, but that “I know we have allies in South Korea and Japan in AUKUS (a pact between Australia, the United Kingdom and the U.S.) with Australia.”

The 10-nation bloc, known as ASEAN, has been useful for the United States in countering China’s influence in the Indo-Pacific. Many member nations have territorial disputes with China, which has become increasingly assertive in pressing those claims.