Four French men kidnapped by al Qaida militants in northern Niger almost two years ago appeared in a video on Saturday appealing to French President Francois Hollande and their employers to continue negotiations to secure their release.

The seven-minute video, posted on a Mauritanian news website, shows the four men - Pierre Legrand, Daniel Larribe, Thierry Dole and Marc Ferret - looking healthy and kneeling in a desert setting with armed men in traditional Bedouin clothing and turbans standing over them carrying kalashnikov rifles.

The video is the first evidence to emerge in nearly 18 months proving the hostages kidnapped by al-Qaida's north African arm (AQIM) are alive.

France's Foreign Ministry said the men shown in the video were the French hostages named and it was working to authenticate when the footage was shot.

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