As anyone who's caught one of her hilarious appearances on The Graham Norton Show will know, Miriam Margolyes definitely doesn't censor herself.

In a new interview, the Harry Potter and Call the Midwife actress has recalled the time that her super-chatty personality earned her a (very mild) ticking off from Queen Elizabeth II.

The incident occurred during a reception at Buckingham Palace to mark British book week around 15 years ago, The Times reports. After the British monarch asked Margolyes, "And what do you do?", the actress replied that she was “the best reader of stories in the whole world."

Queen Elizabeth II then moved on to talk to her next reception guest, a man who helped dyslexic children, but Margolyes butted into their conversation and started asking questions, prompting the monarch to tell her to "be quiet."

"I don’t know what possessed me,” Margolyes recalled. "I behaved in that stupid way that people do when they meet royalty; you lose your marbles. It was a bit pulverizing actually."

Margolyes even admitted that she kept on talking after the Queen asked her not to, saying: "I had verbal diarrhea because I was so embarrassed, I think."

During the same interview, Margolyes expressed her support for trans folks, following in the footsteps of fellow Harry Potter stars including Daniel Radcliffe and Emma Watson, who have voiced their support for the trans community following controversial comments made by the franchise’s creator J.K. Rowling.

“I know what has happened,” Margolyes said of Rowling. “She has a rather conservative view of transgender people. I don’t think I do.”

She added: "I can’t make it out. It's a matter of personal happiness for people and I think that's what you should concentrate on. If you seriously want to become a woman you should be allowed to. You can't be fascist about it. I think it's confusing."

We recently made Miriam Margolyes our British Icon of the Week, rounding up some of the other times she had absolutely no filter.

How do you think you would you respond if Queen Elizabeth II asked you to "be quiet?"