Former First Lady Michelle Obama sledges Donald Trump in new memoir

She’s famed for her intelligence and know-how, but there was one thing even former First Lady Michelle Obama never saw coming.

Michelle Obama has shared brand new insights into her time as US First Lady — and taken a few swipes at current President Donald Trump in the process.

In her new memoir Becoming, Ms Obama has opened up about what her eight-year stint as First Lady was really like.

But while the book charts the 54-year-old’s remarkable journey from childhood in Chicago to a Princeton University education and finally the White House, it also includes a frank admission about one of the mother of two’s biggest mistakes — underestimating Donald Trump.

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In her hotly-anticipated book, Ms Obama describes her first reaction to the news Mr Trump was planning a tilt at the presidency.

Mr Trump revealed his plans to run for office during a heated press conference where he famously described Mexican immigrants as “rapists”.

But at the time, Ms Obama admits she didn’t take the announcement seriously.

“I figured he was just grandstanding, sucking up the media’s attention because he could,” she wrote.

“Nothing in how he conducted himself suggested that he was serious about wanting to govern.”

Ms Obama admits she failed to take Mr Trump’s presidential run seriously. Picture: AFP Photo/Jim Watson

It was an opinion shared by many, and it made Mr Trump’s November 2016 election win all the more surprising

But it was just one of many digs at the current president within Becoming’s pages.

In the book, Ms Obama also described her outrage at Mr Trump’s now infamous “grab them by the p*ssy” tape.

“My body buzzed with fury after hearing that tape,” she said.

Ms Obama was so incensed she decided to mention it during a speech she gave in support of Mr Trump’s rival and fellow presidential candidate Hillary Clinton shortly after the tape was released.

“I felt compelled to try to address Trump’s words directly-to counter his voice with my own,” Ms Obama wrote.

“Since childhood, I’d believed it was important to speak out against bullies while also not stooping to their level.

“And to be clear, we were now up against a bully, a man who among other things demeaned minorities and expressed contempt for prisoners of war, challenging the dignity of our country with practically every utterance.”

Michelle Obama worried about how White House culture might influence daughters Sasha and Malia. Picture: Kevork Djansezian/Getty Images

She also wondered why female voters could have supported Mr Trump in light of his offensive comments about women.

“I will always wonder about what led so many women, in particular, to reject an exceptionally qualified female candidate and instead choose a misogynist as their president,” she wrote.

Ms Obama’s overt criticism of Mr Trump is unprecedented, with no First Lady every attacking a sitting President in a memoir before.

In the book, Ms Obama also slammed the culture within the White House, which she considered to be a bad influence on young daughters Malia and Sasha.

“Barack was now surrounded by people whose job was to treat him like a precious gem,” she wrote.

“It sometimes felt like a throwback to some lost era, when a household revolved solely around the man’s needs, and it was the opposite of what I wanted our daughters to think was normal.”

The Obamas scored a staggering $A82.9 million book deal. Picture: Jim Young/AFP

Becoming has just been released as part of a joint, $US60 million ($A82.9 million) book deal — believed to be one of the most lucrative in history — with former President Barack Obama.

It is expected to sell millions of copies, has already climbed to the top of Amazon’s bestseller list and smashed pre-order records.

The release date of Mr Obama’s book is not yet known, but Penguin Random House has revealed the couple plan to donate much of the proceeds to charity.

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