National security advisor Jake Sullivan said President Biden was doing what he could to "strengthen" the position of Ukraine before he leaves office.

Jake has served as the U.S. National Security Advisor throughout Joe Biden’s presidency. Learn more about his personal life, here.

Outgoing National Security Adviser Jake Sullivan denied reports that the Biden administration is considering returning nuclear weapons to Ukraine, after the country relinquished its stockpile three decades ago after the fall of the Soviet Union.