The seven family members taken hostage Feb. 19. Four of the group are children, the youngest not yet 5 years old, Radio France Internationale said Saturday.
"All our efforts need to be put in to seeing the release of our compatriots," Foreign Minister Laurent Fabius said in the French ambassador's home in the Cameroon capital Yaounde. "In this type of situation you need to have determination and discretion, that's the tactic we follow."
The militant Islamist group Boko Haram is believed to be behind the kidnapping, acting in retaliation for the French military incursion in Mali, officials said.
Shortly after the family's capture, an adult male hostage was made to make a video released on YouTube.
After the man spoke, one of his captors makes several demands for their release.