According to ESPN's Malika Andrews, former President Barack Obama visited with players participating in the Rising Stars Game during NBA All-Star Weekend as part of an NBA Cares event.
Zion called meeting Obama one of the biggest moments of his life, saying: "This could be No. 1. I don't want to say it is No. 1 right now because the draft might be one, but this is definitely top two."
Williamson was taken No. 1 overall in the 2019 NBA draft by the Pelicans in June, and he is quickly developing into one of the NBA's fastest-rising stars.
Per Andrews, Obama spoke with Williamson and Atlanta Hawks guard Trae Young for 20 minutes while helping them fill backpacks for under-resourced students and teachers.
Zion suggested that it was something of a blur, but remembered something in particular that Obama told him: "He said I played great and I kind of zoned out after that. That was all I needed to hear, to be honest."
Obama is a basketball enthusiast and Chicago native who played in high school and famously organized pickup games at the White House during his presidency.
Williamson missed the first three months of the season due to injury, but he has quickly developed into a force for a Pelicans team that is starting to make moves in the Western Conference.
Zion has topped 30 points in each of his past two games, and he is averaging 22.1 points, 7.5 rebounds and 2.2 assists per game in 10 contests.
While Williamson hasn't played enough to earn an All-Star nod, he will get a chance to showcase his skills in the Rising Stars Challenge on Friday night at the United Center in Chicago.
Williamson will share the floor with many of the best young players in the NBA, including Young, Memphis Grizzlies guard Ja Morant and Dallas Mavericks guard Luka Doncic in a Team USA vs. Team World format.
It isn't known if Obama will be present for the game, but if he is, Williamson and the rest of the players will have some added incentive to impress.