US First lady Michelle Obama celebrated her 50th birthday on the weekend with a party at which she danced until midnight and which was attended by artists such as Beyonce, Stevie Wonder and John Legend.

The White House distributed a limited number of invitations to personalities close to the first lady asking them to wear comfortable dancing shoes and spend an evening of “Snacks & Sips & Dancing & Dessert.”

The invitees were admonished to keep their attendance at the Saturday evening event secret and not to publish photos or remarks about it online, a request that apparently was respected by all although the press managed to extract certain verbal details from some of them about the soiree.

President Barack Obama displayed his dancing ability, despite the fact that his wife has much more skill in that regard than he, as she has shown in the past on numerous public occasions.

Party guests questioned by CNN said that the president delivered some heartfelt remarks about his wife to the gathering before hitting the dance floor with the rest of the guests, most of whom partied until midnight.

Beyonce sang at the ceremony, which was paid for by the Obamas and not charged to the public coffers, CNN said.

Michelle Obama was 45 when her husband became president in 2009 and, since then, she has played the role traditionally reserved for first ladies, that is to say one focusing on themes such as education, health and poverty, but with a fresher and more relaxed style than her predecessors.

Born on January 17, 1964, in Chicago as Michelle LaVaughn Robinson, the first lady earned a Harvard law degree and is one of three presidents’ wives to have obtained a graduate degree, the others being Laura Bush and Hillary Clinton.