By Jennifer Newton Nearly 300 schoolgirls kidnapped in Nigeria by Islamist militants could be released in exchange for jailed comrades, a former negotiator has reportedly said. The group snatched the girls from their boarding school in Chibok in the lawless Borno region in the north of the country. A former mediator who once brokered peace talks with the group has told the Telegraph he believes the video, where Boko Haram leader Abubakar Shekau threatens to sell the girls as slaves, shows he plans to use them as ‘bargaining chips’ rather than kill them. Scroll down for video A grab taken from a video obtained by French news agency AFP which shows the leader of Islamist group Boko Haram, Abubakar Shekau (centre), vowing to sell hundreds of captured schoolgirls as sex slaves
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Shehu Sani says the girls are being used as 'bargaining chips'
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Adds they could be released in exchange for jailed Boko Haram prisoners
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More than 300 schoolgirls were snatched by militants last month
Shekau (centre) claimed responsibility on Monday for the abduction of more than 200 schoolgirls during a raid in the village of @placeholder in northeast Nigeria last month