Indonesia's new president says he wants to be called his nickname, and has revealed who first gave it to him: a French furniture buyer.

Joko Widodo, who was sworn in as president on Monday, has long been widely known as Jokowi, a contraction of his two names.

In interviews with local media this week he confirmed he wants to be officially known as Jokowi, saying Widodo would sound "strange."

Kompas daily quoted him as saying a French man gave him the name when he was buying furniture from Jokowi.

The French man was buying on Java island from several people called Joko so he added the "wi" to help him.

The paper said the man, identified as "Bernard", visited Jokowi on Monday in Jakarta.