Former First Lady Michelle Obama caused a stir during her arena book tour on Saturday when she said that marriage inequality can’t be solved by women ‘leaning in’ because ‘that s*** doesn’t work all the time.’

Obama made the comment during her appearance Saturday at the Barclays Center in Brooklyn, where a large crowd of thousands came to see her promotional appearance for her memoir, Becoming.

The former First Lady was commenting about whether women can experience equality in both their marriage and the workplace - ‘that whole “so you can have it all”’, as she referred to it.

‘Nope, not at the same time,’ Obama said.

‘That’s a lie. And it’s not always enough to lean in, because that s*** doesn’t work all the time.’

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Former First Lady Michelle Obama caused a stir during her arena book tour on Saturday when she said that marriage inequality can’t be solved by women ‘leaning in’ because ‘that s*** doesn’t work all the time.’ Obama is seen above on Saturday at Barclays Center in Brooklyn

‘Lean in’ is the phrase that was made popular by Facebook Chief Operating Officer Sheryl Sandberg.

Sandberg’s book, Lean In, was a 2013 best-seller whose aim was to empower women in the workplace.

The book ignited a cultural discussion about challenges faced by women in the business world, including pay disparity and discrimination.

Michelle Obama’s use of the four-letter word ‘s***’ sent the crowd into a frenzy at Barclays Center, according to social media.

‘THE THOUSANDS OF PEOPLE IN BARCLAYS JUST LOST OUR COLLECTIVE S***’ tweeted Jeanna Kadlec.

Sheryl Sandberg’s book, Lean In, was a 2013 best-seller whose aim was to empower women in the workplace

A Twitter user named Megan tweeted: ‘Despite waiting in the rain for an hour to get into the Barclays Center, I was just in the same room as Michelle Obama and she accidentally said “s***” and it was amazing and my life has been forever changed.’

Erin Strecker tweeted: ‘At Barclays tonight, Michelle Obama said: “It’s not enough to Lean In because that s*** doesn’t always work!” Tattoo it on my body!’

Kevin Flynn tweeted: ‘Tonight at the Barclays Center Michelle Obama accidentally said “s***” in front of thousands of people and it ruled.’

The former First Lady's memoir has become the most sold book this year, according to CNN.

As of December 1, Becoming, which hit the market just two weeks ago, has sold more than 1.1 million hardcover copies.

Its sales have outpaced those of the top two political books this year - Michael Wolff’s Fire and Fury and Bob Woodward’s Fear.

The second most popular book in terms of hardcover sales this year is Magnolia Table, a cookbook by TV star Joanna Gaines.

Former first lady Michelle Obama, left, is interviewed by Elizabeth Alexander at the Barclays Center

When factoring in e-book and audio, Becoming has sold a total of more than 2 million copies in the United States and Canada since its November 13 release, according to the book’s publisher, Random House.

The hardcover edition of Becoming is now in its sixth printing - meaning the publisher has had to order more copies so as to keep up with demand.

After the current printing, there will be 3.4 million copies of the book in print in the U.S. and Canada, according to Random House.

Becoming is also number one on the best-seller lists in the United Kingdom, Germany, France, Italy, and other countries.

Michelle and former President Barack Obama each have been working on memoirs this year, for which they negotiated a $65million dollar deal with Crown Publishing Group/Penguin Random House.

His book is expected in 2019.