In the 21-second tape posted on YouTube, the 30-year old French woman is shown seated on the ground dressed in black, and appeals to François Hollande and Abd Rabbo Mansour Hadi to take decisive action to secure her release.
A request taken very seriously by French authorities, "which has mobilized all of its resources to secure the liberation of our compatriot," said Alexandre Giorgini on Monday, deputy spokesperson of the French Foreign ministry, which has authenticated the video.
Isabelle Prime was working as a consultant on a World Bank-funded project, when she was kidnapped in Yemen on February 24 with her translator Sherine Makkaoui.
Men dressed in police uniform stopped the two women as they were driving to work. But since their capture, little information has been disclosed about the identity of the captors.
Makkaoui was later freed in March, in the southern city of Aden.
French President François Hollande has promised to bring Prime back "as soon as possible," meanwhile her father has called on his daughter's captors to be "merciful."