"Both names will be used simultaneously for one year while 'monkeypox' is phased out," the global health organisation said.
The WHO launched a public consultation process to find a new name for the disease earlier this year.
One of the more popular proposals was 'mpox' or 'Mpox' which was put forward by a men's health organisation RÉZO among others. Its director said at the time that the removal of monkey imagery helped people take the health emergency seriously.
Others were farcical such as 'Poxy McPoxface' which alluded to Boaty McBoatface - almost the name of a British polar research vessel after a public vote on the choice.
Monkeypox, discovered in 1958 and named after the first animal to show symptoms, mostly spread in a group of countries in west and central Africa until this year. Now, 110 countries have reported some 80,000 confirmed cases and 55 deaths, according to WHO data.
(Reporting by Shivani Tanna in Bengaluru and Emma Farge in Geneva;)

A group of activists protest outside the offices of the National Center for Preventive Programs and Disease Control (Cenaprece) in Mexico City, Mexico, 21 October 2022. Activists from the LGBT community protested in front of Cenaprece due to the inaction of the authorities in the face of monkeypox, while demanding the arrival of vaccines to Mexico. EPA-EFE/Isaac Esquivel