Actress Isla Fisher was left mortified on Thursday (20Jun13) when she accidentally uttered a curse word during a live family-friendly talk show.

The Australian star let slip an expletive on U.K. Tv show This Morning when she was quizzed about reports suggesting she scolded her The Great Gatsby co-stars Leonardo DiCaprio and Tobey Maguire for making too much noise while partying in their hotel at the Cannes Film Festival in France last month (May13).

When asked if the story was true, she replied, "Yes, but in my defence, we didn't actually... It was my husband and I - we did put on our robes but we did it more for a joke, we didn't actually b**lock them."

Upon realising her slip, Fisher immediately gasped and covered her mouth with her hands, exclaiming, "I'm so sorry, I'm so so sorry! I'm Australian. We didn't tell anyone off. I didn't finish it (the story)! I didn't quite finish it! Oh no!"

Fisher added, "If anyone writes any letters in, I was pre-warned not to (swear). I'm so sorry!"

Host Phillip Schofield quickly wrapped up the interview by plugging the star's upcoming movie Now You See Me, and an embarrassed Fisher quipped, "But you might not see me ever again!"