Michelle Obama, the wife of US President Barack, has expanded her social media presence by joining Snapchat.

The First Lady of the United States shared a selfie with her first post on the messaging service, before announcing that she will appear on Carpool Kareoke with British TV host James Corden.

A spokeswoman for Mrs Obama said her Snapchat followers will see images from her upcoming trip to Liberia, Morocco and Spain to promote education for girls.

Mrs Obama's teenage daughters Malia and Sasha will accompany her on the trip, while actresses Meryl Streep and Freida Pinto will also make guest appearances.

The First Lady will also share Snapchat images of the White House kitchen garden and showing the Obama family's dogs Bo and Sunny, her spokeswoman said.

Mrs Obama, 52, is an active social media user with some 4.58 million followers on Twitter and five million on the photo-sharing app Instagram.