In a statement late Sunday night, Kristina Schake, the first lady's communications director, said the Academy Awards had approached the first lady about being a part of the ceremony.
"As a movie lover, she was honored to present the award and celebrate the artists who inspire us all -- especially our young people -- with their passion, skill and imagination," Schake said.
Speaking to the National Governors Association again Monday morning, Obama joked about her late night gig.
"I hope you all got some rest after last night. We had a good time," she said. "Little tired. If you noticed, I stayed up a little bit later. Little bit longer than I had anticipated but it was well worth it. "
Her surprise appearance was kept secret by the White House--even the press pool assigned to cover the Obamas on Sunday was not told beforehand about the event.
According to The Hollywood Reporter, the idea for Obama to co-present the night's final award came from Harvey Weinstein, a film executive and big fundraiser for President Barack Obama. To keep it secret, Academy Award producers flew to Washington in a borrowed jet and privately met with Weinstein and staff for the first lady at the White House to work out the details.
To keep the appearance on the hush-hush, the Academy stated in a press release on the Friday before the show that Nicholson would present the best picture award with actor Dustin Hoffman. And just in case they lost the White House signal at the Dolby Theatre in Hollywood, Nicholson was holding an envelope with the winner, as well.
"I loved that we pulled it off," Academy president Hawk Koch told The Hollywood Reporter.
Asked after the show what it was like to hear the first lady announce that "Argo" had won best picture, Ben Affleck--who starred in, produced and directed the film--said it was an honor.
"Honestly, I was just asking these two guys (co-producers George Clooney and Grant Heslov) outside, was that Michelle Obama? The whole thing kind of alarmed me at the time. But in retrospect, the fact that it was the first lady was an enormous honor and the fact that she surrounded herself by service men and women was special and I thought appropriate. Anyway, it was very cool."