Streaming video of Conan O'Brien and President Obama at the gala with attitude in D.C.
Credit: Kevin Mazur/WireImage; Steve Granitz/WireImage

It’s a Hollywood-Washington mash-up that always teeters on becoming a smash-up.

Conan O’Brien brought the late-night comedic chops as host of the White House Correspondents Dinner on Saturday night in Washington D.C.

But it was President Obama who got in the best zingers – much to the delight of the famous faces in the crowd.

“I just witnessed our President deliver the funniest speech I have ever heard,” Tweeted Katy Perry.

Then O’Brien had his chance.

“Right now – Conan. Is killing it!!!” added Julia Louis-Dreyfus on Twitter.

It was definitely a star-studded night. Look among the tables of politicos for the likes of Sofia Vergara, Rebel Wilson, Connie Britton, Amy Poehler, Jessica Pare, Julie Bowen, Kerry Washington and Hayden Panettiere.