Michelle Obama will star in a new documentary out next week which follows the former first lady's global book tour for her smash-hit memoir, Netflix said Monday.

"Becoming," out May 6, is the Obamas' latest collaboration with the streaming giant after last year's "American Factory," which won the best documentary Oscar in February.

The movie "shares the stories of the amazing people I met after the release of my memoir," tweeted Obama following the surprise announcement Monday.

"During this difficult time, I hope you'll find some inspiration and joy in this film."

The book of the same name by Obama -- America's first African American first lady and wife of the first black US president -- became a publishing sensation upon its release in 2018, selling more than two million copies in North America in two weeks.

Obama toured 34 cities over several months to promote the book accompanied by cinematographer Nadia Hallgren, who makes her feature directorial debut with the "rare and up-close" documentary.

The film chronicles Obama's "current experience -- where she is in this moment and the way she's reflecting on the entirety of her life, not just her years in the White House," said Hallgren.

The producers said the movie is a "portrait of a moment in time told through Mrs Obama's story."

Obama added: "I treasure the memories and that sense of connection now more than ever, as we struggle together to weather this pandemic."

"It's hard these days to feel grounded or hopeful, but I hope that like me, you'll find joy and a bit of respite in what Nadia has made."

The first offering from the former first couple's Higher Ground Productions company, "American Factory," told the story of a manufacturing plant in the US Midwest reopened by a Chinese billionaire.