HMD, a Finnish start-up, will make the phones. However, Nokia will receive royalty payments for every branded phone and tablet sold.
Nokia has not invested in HMD, nor is it a shareholder.
HMD appointed Mother to its global creative business after calling a pitch in September.
Brad Rodrigues, interim president at Nokia Technologies, said: "We've been overwhelmed by the enthusiasm shown around the world for the return of the Nokia brand to smartphones.
"The HMD Global team has the ambition, talent and resources to bring a new generation of Nokia branded phones to market, and we wish them every success. I'm sure our millions of Nokia fans will be excited to see their new products!"