Obama, a bit tongue-in-cheek, explained how difficult it was to say no when Clinton invited him to speak at the Clinton Global Initiative last month.

“I think everyone knows what it’s like when Bill Clinton asks you to make a commitment. He looks you in the eye; he feels your pain. He makes you feel like you’re the only person in the room,” Obama said. “What could I say? I was vulnerable, just as all of you have been vulnerable, to his charms.”