London(CNN) Michelle Obama has revealed Queen Elizabeth II's surprising view on royal protocol at a speaking engagement in London on Monday.
The former US first lady recalled worrying as she prepared to be picked up by the British monarch in her car during a visit to Windsor Castle in 2016, reports the UK's Press Association.
"So I had all this protocol buzzing in my head, and I was like 'don't trip down the stairs and don't touch anybody, whatever you do,'" Obama said. "And so the Queen says 'just get in, sit wherever' and she's telling you one thing and you're remembering protocol and she says 'Oh it's all rubbish, just get in.'"
Obama also revealed husband and former US President Barack Obama is a big admirer of the Queen because she reminds him of his grandmother Toot.
"She's smart and funny and honest," she said. "He is a huge fan for sure."
CNN has reached out to Buckingham Palace for comment.
Obama was speaking about her memoir "Becoming" at the Royal Festival Hall in London to a sell-out crowd.
The event was hosted by author Chimamanda Ngozi Adichie, and Obama covered a range of topics.
When Adichie asked about her role as a "symbol of hope," Obama revealed that she sometimes still struggles to believe in herself.
"I still have a little imposter syndrome, it never goes away, that you're actually listening to me," she said. "It doesn't go away, that feeling that you shouldn't take me that seriously."
The pair also discussed the current political situation in the US and the idea of progress in civil rights.
"My grandparents' lives were affected by Jim Crow, we mistakenly thought that Barack Obama was going to erase hundreds of years of history in eight years, that is ridiculous," she said.
"We are putting down markers, we make progress and going backward doesn't mean the progress wasn't real. It just means that it's hard, what we are trying to do is shift culture."
Obama also took the opportunity to address young black women, who she said "become a caricature."
"We are angry, we are too loud, we are too everything and I experienced that, just campaigning, just speaking truth to power, how dare I have a voice and use it?" she said.
However, there were lighter moments too, as Obama remembered trying not to become even more famous than she already is.
"If you're thinking about my thoughts when I come out on stage it's 'don't fall,'" she said. "One of my primary goals for the eight years was to never become a meme."
Michelle Obama's memoir has become the best-selling book of the year in the US, surpassing Michael Wolff's "Fire and Fury" and others.