Blake Lively flashes her underwear at the White House

Blake Lively had a mini wardrobe slip at the White House!

The 28-year-old actress hit the White House State Dinner for Canada with her husband, Ryan Reynolds, on Thursday night and she accidentally had a little dress slip. The stunning star was walking into the event in a glimmering, silver dress with long sleeves and a thigh-high slit in the front. As Lively moved, the dress unfortunately moved too and revealed her SPANX undergarments.

Thankfully, her undies were of the nude variety and looked a lot more like cycling shorts than tiny knickers. Crisis averted!

Lively and her Canadian hubby definitely weren't the only big names rubbing elbows with the Obamas and Canadian Prime Minister Justin Trudeau. Mike Myers, Sandra Oh and more popular stars also attended.

Despite the undie snafu, Lively looked absolutely gorgeous at the event. She paired her silvery gown with a set of chandelier earrings and polished off her look with long, blonde locks and pink lips.

Well done, Blake.

PHOTOS: Inside the White House State Dinner