Magical memories for Michelle Obama as she donates her iconic inaugural ball dress

Michelle Obama and her mother Marion admire the Jason Wu gown she wore to the inaugural ball held in honour of her husband in 2009

It's the dress that will be forever be associated with the election of the United States' first African-American president. 

And the beautiful white one-shouldered chiffon gown worn by Michelle Obama for her dancing debut as first lady at her husband's inauguration ball was back in the spotlight again this week.

In keeping with tradition, the mum-of-two donated her Jason Wu inaugural ensemble to the Smithsonian Museum on Tuesday, where it will go on public display as part of a new first ladies exhibit.

Joined by her mother Marion and the talented 27-year-old designer at Tuesday's unveiling, Michelle openly talked the first time she wore the Swarovski crystal-studded dress, as memories came flooding back of that chilly night of January 20, 2009.

After revealing how hectic the day was – she had less than an hour to get ready for the ball – the former lawyer said: "I'll never forget the moment that I slipped on this beautiful gown.

"I remember how just luscious I felt as the president and I were announced onto the stage for the first of many dances. And I'll cherish that moment for the rest of my life. This gown is a masterpiece."

Michelle's selection – displayed with her white Jimmy Choo peep-toe heels, thin diamond bracelets, a ring and earrings – is one of a number of inaugural dresses displayed in the collection.

All first ladies since 1912 have contributed to the exhibit, and visitors will also be able to see Jackie Kennedy's 1962 silk gauze ensemble and the red lace dress Laura Bush wore on her big night in 2001.

For couturier Jason, who only opened his first store four years ago, Tuesday's unveiling had a profound impact in terms of understanding his creation's historical impact.

Speaking of his surprise when he turned on the TV to see the country's new first lady in his design, the Taiwan-born talent admitted: "It really dawned on me today that the dress will outlive me."